The confusion is not accidental. It stems from a lack of understanding of what autonomy in healthcare truly means and how it should be exercised within a system that values ​​evidence-based practice and patient wellbeing. To understand this conceptual trap, we need to distinguish between two very different types of autonomy: formal autonomy and substantial autonomy.

The difference

Formal autonomy is a relatively simple concept: it’s the legal and ethical right we have to make our own decisions, including in healthcare. It’s an important historical achievement, the result of decades of fighting against various forms of authoritarianism, including medical authoritarianism, and is an unquestionable pillar of the modern therapeutic relationship.

Substantial autonomy, on the other hand, is much more complex. It’s not limited to the right to choose, but rather the effective ability to make informed, deliberate choices aligned with one’s values ​​and life goals, based on a clear understanding of the situation. This means genuinely understanding the available options, their risks and benefits, the evidence supporting them, and the consequences of each alternative.

A person may have full formal autonomy – such as the right to refuse a vaccine – without having substantial autonomy, if their decision was based on false information, irrational fears, or a distorted understanding of the risks involved.

Take my driver’s licence as an example: while I regularly drive my car, I have a dual license, which means I have the formal autonomy to decide to ride a motorcycle at any time. But, substantially, it would be risky (for me and others) to do so without further training, since I have not touched a motorcycle since I took the practical test in 2007. The right to do something does not automatically imply the ability to do it safely or beneficially.

Anti-vaccine movements and advocates of alternative therapies discovered some time ago that invoking “patient autonomy” is a powerful rhetorical strategy. By framing dangerous or unscientific decisions as ‘exercising individual freedom’, they can shift the focus from (absent) scientific evidence to issues of personal rights. “You have the right to choose”, they say, transforming a decision that should be based on the best available evidence (and informed dialogue with qualified professionals) into an ideological issue of freedom versus oppression.

This strategy is effective because it leverages two psychological tendencies: a natural aversion to explicit paternalism and a tendency to overestimate one’s ability to evaluate complex information, especially in areas where one lacks expertise. “You know what’s best for you” sounds empowering and respectful. But in practice, it can be a subtle way of abandoning a patient to their own devices amidst an ocean of misinformation.

The problem is compounded when the rhetoric of autonomy is used to legitimise the refusal of interventions with clear and well-documented benefits, or the acceptance of interventions of dubious benefit, proven ineffective, or even dangerous.

Uninformed choice

Here we arrive at an important paradox: defending formal autonomy without guaranteeing the conditions for substantive autonomy can actually undermine true freedom of choice. A person who decides not to vaccinate their child based on the belief that vaccines cause autism (a claim already widely refuted by science and debunked as a fraud) is not exercising genuine autonomy, is being misinformed and, consequently, may be acting against the best interests of their child and public health.

This doesn’t mean we should return to medical paternalism. It means we need a more sophisticated and ethically robust approach, one that recognises that true autonomy requires quality information, time for deliberation, and support to understand complex options. This is where the concept of shared decision-making comes in.

Shared decision-making is not simply informing the patient and letting them decide. It is a structured process that includes: two-way communication about the clinical condition; clear presentation of evidence-based options (including the option of not intervening, when appropriate); exploration of the patient’s values ​​and preferences; collaborative deliberation; and implementation of a consensual decision. It is a process that takes time, requires specific skills, and demands appropriate communication tools. It is a model that aims to empower the patient through knowledge and dialogue, not simply by delegating choices.

What often happens in practice is that healthcare professionals, pressed for time, lacking communication training, or unsure how to deal with patient resistance, end up using the rhetoric of autonomy as a way to avoid conflict or to avoid a deeper professional responsibility. “The patient doesn’t want to get vaccinated? That’s fine, they have the right to choose.” This may seem respectful, but it can be a disguised form of abandonment.

True respect for patient autonomy would require investigating the reasons for the refusal, clarifying doubts, correcting incorrect information, and helping the patient make a genuinely informed decision. This is laborious and doesn’t always work, but it’s what distinguishes patient-centered care from mere formalism.

The problem becomes even more serious when we consider that the ability to exercise substantial autonomy is not equal for everyone. Formal autonomy establishes the universal right to choose and operates according to the principle of equality, treating everyone equally. This approach can end up perpetuating inequalities by failing to consider different individual needs.

In contrast, substantial autonomy is based on the principle of equity, recognising that each individual requires different types and levels of support to exercise full decision-making capacity. The lack of this support disproportionately affects the most marginalised populations.

Structural dimension

This asymmetry in the ability to exercise substantial autonomy reveals a structural issue often ignored in debates on patient rights: autonomy does not exist in a vacuum, but is shaped by material, educational, and social conditions. A working mother who needs to decide about her child’s vaccination but only has access to WhatsApp groups is not operating in the same realm of possibilities as a specialist with direct access to scientific literature and training to interpret it.

This disparity manifests itself in particularly perverse ways in the context of pseudotherapies. Patients in vulnerable situations (whether due to serious illness, financial constraints, or low educational attainment) become prime targets of discourses that promise to “return control” through alternative choices. The rhetoric of autonomy, in these cases, functions as a smokescreen that conceals the exploitation of others’ vulnerability.

Healthcare institutions, in turn, may condone this conceptual confusion, albeit passively. By adopting a stance of apparent neutrality (“we respect the patient’s choice”), they absolve themselves of the responsibility to educate, clarify, and, when necessary, constructively challenge decisions based on incorrect information. This stance constitutes a subtle form of negligence.

The proliferation of health discourse on the internet has exacerbated this paradox: we’ve never had so much access to medical knowledge, but it’s also never been so difficult to distinguish reliable information from sophisticated misinformation. Social media algorithms, designed to maximise engagement, often amplify sensationalist and emotionally charged content to the detriment of more sober and factual scientific information. In this context, defending only the patient’s formal autonomy, without concern for the quality of the informational environment in which they interact, is like offering the freedom to swim in waters known to be unsafe for swimming.

There is a system that claims to respect autonomy while systematically failing to create the conditions for its genuine exercise. Even more troubling is when this same deficient structure is invoked to justify harmful decisions. “The patient was informed and chose this” is the phrase that ends the discussion, regardless of the quality of the information provided or the conditions under which the “choice” was made.

Ethical, effective, and evidence-based healthcare communication thus becomes a technical skill as important as mastery of clinical procedures. It’s not an optional soft skill, but an essential tool.

Final considerations

The misunderstood autonomy trap reveals the conflict between democratic ideals of individual freedom and the reality that genuinely free choices require specific conditions that are not available to everyone.

Overcoming this trap requires more than goodwill or occasional adjustments to clinical practices. It demands a reorganisation of how we think about healthcare, recognising that substantial autonomy is a goal to be built, not a natural condition we passively accept.

This implies investments in health education, the development of more effective and accessible communication tools, training professionals in communication skills, and, fundamentally, the recognition that health is a common good that transcends individual choices, with significant collective implications.

True autonomy in health is not achieved simply by declaring it a right for all human beings, but rather by establishing it as a real possibility through social and institutional structures that give it substance. This is perhaps one of the most urgent and complex challenges in contemporary healthcare.

This story was originally published by Revista Questão de Ciência in Brazil. It is translated and reprinted here with permission.

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Following Oxford, she embarked upon a writing career, finding fame in 1991 with The Beauty Myth – a feminist blockbuster and international bestseller, which argued that beauty is a socially-constructed concept designed by the patriarchy to shackle women. Even then, there were warning signs that the academia flowing through her veins might have been taking a few shortcuts. The book claimed 150,000 women die every year in the US from anorexia, citing the American Anorexia and Bulimia Association. However, the organisation says she misquoted them – the 150,000 figure referred to sufferers, not fatalities. The actual number of annual deaths was closer to 100.

The error wasn’t a one-off: Wolf also claimed that 3.5 million Brits suffered with anorexia or bulimia – which in 1991 would have accounted for 6% of the UK population. When challenged, she said she’d calculated the figures herself by extrapolating data from a single clinic. Experts did not agree that this was a realistic number. In fact, of the 23 statistics cited in The Beauty Myth, 18 were incorrect – and on average, Wolf’s figures were 8 times larger than the real numbers.

Two years later, Wolf published her follow-up, Fire with Fire, espousing what she called “power feminism”. It argued that Anita Hill’s sexual harassment accusation against US Supreme Court nominee Clarence Thomas provoked a ‘genderquake’ that turned American women into ‘the political ruling class’ – an idea other feminist writers described as “grossly exaggerated” and a “dubious oversimplification and highly debatable assertion”.

The die was cast, with her feminist academic peers now describing her as “a sloppy thinker and incompetent writer” – although such verdicts did little to diminish her growing reputation as a feminist public intellectual across the course of several more books. In 2007, she wrote her critique of fascism, The End of America, comparing post-9/11 politics in the United States to what she described as a 10-step checklist of fascism through history. A review in The Atlantic pointed out that the historical parallels she lists between historical dictators and modern American politicians were constructed by cherry picking data and misusing sources. By 2010, Wolf was giving interviews about how Barack Obama’s presidency resembled Adolf Hitler’s dictatorship.

In October 2014, Wolf took to Facebook to just ask questions about videos that showed ISIS beheading journalists from the US and UK. According to Wolf, the videos were staged by the US government – no such journalists were killed. Those grieving parents? Actors.

When criticised for expressing such opinions, Wolf doubled down:

All the people who are attacking me right now for ‘conspiracy theories’ have no idea what they are talking about … people who assume the dominant narrative MUST BE TRUE and the dominant reasons MUST BE REAL are not experienced in how that world works. I stand by what I wrote.

Shortly afterwards, she deleted the post, and retracted her statements, saying the videos were “not yet independently confirmed by two sources as authentic” and claiming that the single source for the videos was in the pocket of the US government. That also was not true – the videos had been independently verified.

The same year, she claimed that US troops dispatched to West Africa to help treat Ebola were actually ordered to import the virus back to the US for use as a bioweapon to secure a military coup on US soil. Elsewhere in 2014, she claimed that the Scottish independence referendum was rigged in order to keep Scotland under control of the Westminster.

Academic death recorded

Then came the pivotal moment in Wolf’s career. After finally completing her doctorate at the University of Oxford in 2015, Wolf turned her thesis into a book, Outrages: Sex, Censorship, and the Criminalization of Love. The book, and her PhD, was a study into how homosexuality had been punished by British society – including the “execution” of “sodomites”. Oprah’s magazine listed it as one of their top books of the year. However, the very next day, all copies were recalled from US bookstores, and pulped.

The reason for this change in fortune was Wolf’s May 2019 interview with BBC radio presenter Matthew Sweet, in which Sweet highlighted that one of the central lines of evidence Wolf relies upon to prove the persecution of homosexuals was a list she’d found of several dozen executions.

“I don’t think you’re right about this”, Sweet told her – live on air – before explaining that one of the people her book claims was executed in the 1860s… had actually been released. In fact, Wolf had misunderstood the text of her main source: in each of the cases, where a victim was listed as “death recorded”, the judge had seen fit to issue a pardon, while fulfilling a legal requirement to write “death” in the records. The radio interview makes for excruciating listening.

It only gets worse: the crime in each case was listed as ‘sodomy’, but despite what Wolf had assumed, this didn’t mean homosexuality. Sodomy was a broad category at the time, covering a range of sex crimes. Wolf was, as historian Fern Riddell put it, conflating “child rapists and those taking part in acts of bestiality as being gay men in consensual relationships” – all in order to decry the persecution of homosexuality. This was the central tent pole of Wolf’s book – and of her doctoral thesis – and she hadn’t checked what the terms meant. 

To say Wolf took this huge public humiliation badly is an understatement. Two months later, in July 2019, she was spiralling into conspiratorial whirlpools, including warning against the dangerous rollout of 5G:

It was amazing to go to Belfast, which does not yet have 5G, and feel the earth, sky, air, human experience, feel the way it did in the 1970s. Calm, still peaceful, natural, restful.

The sentiment once again showed her lack of understanding of history, given that Belfast in the 1970s was rather famously not very calm, and rarely peaceful.

Wolf and Covid

That was late 2019, and already a novel virus was evolving in a wet market in Wuhan, which would capture the mind of this conspiracy-prone writer. The pandemic was a perfect storm for Wolf, with her overestimation of her own ability to figure out what’s true, her questionable research methods, and her instinct for identifying in the shadows sure-fire signs in of the looming totalitarian regime – especially so soon after the high-profile humiliation she’d suffered over her most serious academic work.

From March 2020, her Twitter, Facebook and Telegram channels became a clearing house for misinformation about the virus, the wearing of masks, the effectiveness of lockdowns, and the safety of vaccines. She told her 140,000 Twitter followers that Covid-19 restrictions were tantamount to the Jim Crow laws. She explained how terrifying it was that in these post-mask times, “children don’t have the human reflex that they when you smile at them they smile back” because she was “seeing kids with their lower faces hanging inertly, absolutely unmoving facial muscles, when they take their masks off”. She explained that, having read the Moderna website, “the mRNA is not actually a vaccine but a software platform”. She told her followers:

I actually work with developers who create software so I understand how dangerous it is to have a tech in one’s body that can receive ‘uploads’.

For Wolf, these revelations apparently finally made sense of a conversation she claims to have overheard in a restaurant in Manhattan in 2019, explaining to her Twitter followers in February 2021:

Terrifying. Also confirms/explains the conversation I overheard in a restaurant in Manhattan two years ago in which an Apple employee was boasting about attending a top-secret demo. They had a new tech to deliver vaccines with nanoparticles that let you travel back in time. Not kidding.

It’s hard to know what the conversation was that she overheard. Perhaps it was a conversation about Apple’s “Time Machine” backup feature, or perhaps relevant is the fact that the movie Avengers: Endgame came out in 2019, in which the heroes essentially inject themselves with nanoparticles in order to travel back in time.

In April 2021, she made international headlines after using her former feminist credentials to amplify myths that the vaccines were causing infertility in women – which they weren’t. Later the same month, she claimed Anthony Fauci doesn’t work for the US, because he had loyalties to Israel that interfered with service to public health. Wolf, it’s worth pointing out, is Jewish – a fact she used to deflect criticism for sharing what some people read as an obvious antisemitic trope.

The claims continued, including claiming that “unvaccinated people report feeling ill when in enclosed rooms for a length of time with vaccinated people” because “the virus could have been a Chinese bioweapon”. She even highlighted the urgency of keeping the urine and faeces of vaccinated people out of the general sewage supply while tests were done to measure its impact on non-vaccinated people through drinking water.

It is no surprise, then, that her political allegiances have shifted throughout this time – she appeared on The Charlie Kirk Show in May 2022 to warn about “military-age men pouring over the border from places like Afghanistan and Ukraine” in order to be armed on behalf of the World Health Organization. She has appeared on Fox News, and Tucker Carlson, and became a regular contributor to Steve Bannon’s War Room. She even appeared as an expert on Infowars, with Alex Jones. Then, in 2024, this former feminist trailblazer threw her weight behind two men who could hardly be considered allies of equality: Donald Trump and RFK Jr. Even that final conclusion of her political transition didn’t happen without suspicious circumstance, as she explained last October:

I endorsed Pres Donald Trump yesterday. Today all day my phone froze, the cursor on my computer started wandering around the desktop, and my wifi continually disconnected. All coincidentally.

As the New Statesman summarised: “Perhaps it’s not that Wolf is a feminist who’s degenerated into conspiracism, but instead that she’s a conspiracy theorist who happened to fall into feminism first.”

The post Who’s afraid for Naomi Wolf? The fall of a feminist icon into a conspiracist rabbithole appeared first on The Skeptic.

With the interests in longevity on the rise, we are bound to see both scientifically promising treatments (by this I mean a realistic and incremental improvement in health outcomes at older ages) and a large helping of pseudoscience, as well as everything in between.

On one hand we have things like tech-bro Bryan Johnson infusing himself with his son’s plasma as a “biohack” to reverse aging – a regime he later stopped, because (surprise, surprise) it didn’t work. On the other hand, we have some scientifically plausible interventions such as epigenetic reprogramming (like Yamanaka factors) or various possible senolytic drugs. Currently, these interventions are still in development and have not been widely implemented in humans, for various reasons. If history is any guide, most of these interventions will quietly be shown to be ineffective, unsafe, or both.

One of the possible useful interventions against ageing is calorie restriction (CR), which has been studied for almost a century for its anti-ageing properties… but the operative word here is “possible.” Research has established that, under laboratory conditions, CR can lead to longer lifespans in organisms such as research worms (C. elegans), flies (D. melanogaster), and mice (M. musculus). Effectiveness, however, is less apparent in primates and people, and there are still many unresolved questions underlying the concept.

One long-standing problem with CR is that very few people would be willing to comply with the protocol. Simply put, it is difficult to eat as little as would be necessary to match a lot of the research done on animals. With unclear or questionable benefits, it turns out to be a big ask. Given this, there has long been an interest in developing some kind of pharmaceutical mimic of CR; something that would provide the benefits of CR without the pesky need to eat like a person on a hunger strike.   

There have been a number of proposed molecules to mimic CR over the years, but one that wasn’t on my radar until recently is Lithocholic Acid (LCA). Like many other hopeful CR-mimicking molecules, it has had some interesting metabolic functions and relatively novel research behind it. LCA is not directly synthesised by our bodies. Instead, it is derived from the microbiota of the gut, which is great because I need more ways to worry about whether or not my gut is healthy. The reason LCA is thought to be capable of mimicking CR is in its ability to activate an enzyme known as adenosine monophosphate activated protein kinase – which is a mouthful, so we usually just use the initialism AMPK.

AMPK is a really interesting enzyme, and I’m sure it has taken up a significant amount of the career of dozens or even hundreds of researchers. AMPK has extremely wide ranging and complex metabolic effects, including playing a role in regulating glucose uptake, glycolysis, fatty acid synthesis, cholesterol regulation, protein synthesis, autophagy, sirtuin activation, and more. Obviously, there are dozens – if not hundreds – of downstream effects from AMPK regulation, as it is implicated in all of these metabolic pathways. Further, these same pathways are thought to be affected during times of calorie restriction: LCA levels increase under calorie restriction conditions in some models, and has been proposed as one upstream signal that may contribute to AMPK/sirtuin activation thereby affecting all the downstream metabolites. All of this makes lithocholic acid of great interest for ageing research and a plausible target for pharmaceutical intervention.

Naturally, scientists began looking into LCA. Research has indicated a similar pattern to CR as one might expect: flies and worms improved in various ways and lived longer, consistent with CR research; mammals, however, presented differently. In one December 2024 study, while LCA treatment increased muscle strength, ability to run, and increased mitochondria activity, there was no mention of mice living longer. Given the fact that mice were a subject of the study, it would be odd if they weren’t looking for extended lifespan. My guess, it just wasn’t statistically significant.

There are other reasons we should be skeptical of something like LCA as a treatment for longevity. One of these reasons is the fact that LCA seems to be capable of both promoting tumour formation and suppressing it based on context (concentration and the microenvironment in which it is found), and it may very well be hepatotoxic. All of this is consistent with the pattern of many such hopeful longevity molecules: there is a scientific plausibility for a desirable treatment, a small amount of hype in industry and among researchers, a few headlines come out about another “fountain of youth,” and then nothing comes of it, or it only has niche applications.

As a final note I am happy to say LCA has yet to be picked up by the supplement industry and is only really available for purchase as a laboratory reagent (please don’t ingest reagents). I wouldn’t be surprised if some biohacker or supplement company tries to market it as “SUPER AMPK” at some point, but at least now you’ll know to roll your eyes and pass up their offer.

The post Lost in translation: why most longevity breakthroughs don’t become therapies appeared first on The Skeptic.

What qualifies as a chronic disease – sometimes used interchangeably with ‘non-communicable disease’ – varies, but it is generally any long-lasting illness that requires continuing care, with some definitions specifically excluding infectious diseases. In the US, 8 of the 10 leading causes of death in 2023 were related to chronic disease, including heart disease, cancer, and stroke. That chronic disease accounts for so many deaths in the US may seem to paint a dismal picture for population health, however this fact must be viewed in the proper context, to fully understand the landscape of health in a developed nation.

The Epidemiological Transition

The Epidemiological Transition is a theory that was first proposed in 1971 by Abdel Omran. It describes how, as a country develops, advancements in healthcare and public health allow it to better treat and prevent infectious disease, significantly lowering their mortality. This drives increases in lifespan, which allows more time for people to develop chronic diseases whose mortality occurs on a longer timescale.

At the time of writing, we have not yet discovered the secret to immortality. Everyone will die from something. The longer somebody lives and the better we are at managing infectious disease, the more likely it is that they will die, at least in part, from a chronic disease. It is therefore not inherently a bad thing that so many of the leading causes of mortality are chronic diseases; it can be seen as a sign of how adept our public health and healthcare infrastructures have become in controlling some of the greatest historical threats to human life.

With that in mind, let’s look at the claim that 90% of US health expenditures are for people with chronic and mental health conditions. This figure comes from a 2017 chartbook from the Rand Corporation titled ‘Multiple Chronic Conditions in the United States’. The first issue is that the 90% figure refers to care for people who have chronic and mental health conditions, not necessarily care for those conditions. While it also establishes that people with these conditions do use health services more, the 90% figure does not tease out the expected baseline cost of care.

This figure also requires the context of what percentage of people have chronic or mental health conditions. The same chartbook reports that in 2014, 60% of adults in the US had at least one chronic condition, which means 90% of healthcare spending went to care for 60% of adults. They also report that the share of that spending increased based on the number of concurrent chronic conditions, and that having multiple chronic conditions is heavily associated with age.  81% of adults 65 and older had multiple chronic conditions, compared to 42% of adults overall. People with one or two chronic conditions represented 31% of the population, but only accounted for 23% of spending, while people with five or more chronic conditions represented only 12% of the population and whose medical care accounted for 41% of healthcare spending.

Therefore, when we look at that 90% figure in context, we can see how significant an impact age has on healthcare expenditures. This lines up with what we would expect from Omran’s theory of the Epidemiological Transition, and may change how we look at policy and public health efforts to address the underlying challenges.

Prevalence

Prevalence is a measure of disease frequency commonly used when discussing chronic disease. It refers to the total amount of a given disease within a population at a moment in time, like the number of people in the UK who are currently living with type 2 diabetes. While it is an important figure for illustrating the impact of a disease on the population and healthcare infrastructure, it can be counterintuitive.

Kennedy does not provide any evidence for his claim that prevalence of chronic disease was as low as 3% during the John F. Kennedy administration, but it is correct to say that the reported prevalence of chronic disease in the US has risen since the 1960s. While this could be a result of more people developing chronic disease, there are several positive reasons that also contribute to increases in prevalence.

The longer somebody with a chronic disease lives, the longer they are counted in prevalence numbers for that disease. As a result, increases in treatment effectiveness and accessibility can lead to larger prevalence numbers. For example, the yearly number of new HIV infections in the US fell by 73% between 1985 and 2019, but prevalence remains high, with roughly 1.2 million people living with HIV, due to highly effective treatments that significantly extend life expectancy.

Another positive contributor to increasing prevalence is improvements in screening. In 2016, the US Preventative Services Task Force recommended physicians screen adults for depression. After implementing that screening, a large healthcare system in Northeastern Ohio saw depression diagnoses rise from 1.7% of monthly patients to 2.9% of monthly patients. The number of people living with depression did not change, but more of them were being counted and more of them could seek care for the condition.

A similar effect is seen when there are changes in diagnostic criteria. For example, The World Health Organization puts out a set of guidelines called the International Classification of Diseases and Related Health Problems (ICD). A study of 85-year-olds in Gothenburg, Sweden compared how different sets of criteria for classification affected the recognized prevalence of dementia, including using two versions of the ICD. Classifying cases according to the older ICD-10 placed the prevalence at 20.5%, while classifying the same cases using the newer ICD-11 placed the prevalence at 36.4%. As our understanding of disease changes, we may recognise new or early symptoms that widen the scope of diagnosis. Just like with improved screening processes, the real number of people with dementia did not increase, we just got better at recognising the disease.

The reality

Is the prevalence of chronic disease in the US going up entirely because of these positive health advancements and the increasing age of the population? Is all this worrying over chronic disease for nothing? Probably not. The reality is that there have been major improvements in some areas, while others have struggled. While heart disease is the number one cause of death in the US, its mortality fell 66% between 1970 and 2022. However, these advancements in health are not always equitably distributed across the population, and we cannot ignore the mounting economic costs of treatment for chronic diseases where increased prevention efforts could be more effective.

While Kennedy’s stated ethos of strengthening our approaches to prevention is welcome, his actions tell a different story. From halting meetings of the US Preventative Services Task Force, to cutting funding for mRNA vaccine development, it is difficult to see how his policies could ‘make America healthy again’.

Public health has been swimming against a tide of misinformation in the wake of the Covid-19 pandemic, and Kennedy has been a valuable ally for the wrong side of that equation. At the same time, much of the messaging around chronic disease predates his time with Health and Human Services, including the major claims examined in this article. If the field of public health is to preserve credibility in the face of heightened scrutiny and mistrust, it is vital that we put our messaging in the proper context. Our communications must do a better job of walking the line between urgency and fearmongering.

The post The rise in chronic disease doesn’t necessarily mean we are getting sicker appeared first on The Skeptic.

The post, which already has over 17,000 likes, highlights a study conducted in Brazil that suggests regular consumption of low- or no-calorie artificial sweeteners can accelerate cognitive decline, affecting memory and verbal fluency. The results were obtained from monitoring more than 12,000 people over eight years.

Of course, the post also presented information about the study’s limitations. However, what caught my attention most – and what I consider noteworthy – was the engagement of several internet personalities linked to evidence-based medicine, such as Cadu Viterbo and Laura Marise, among others, who attempted to clarify why the post was problematic. This is because, at many points, even using the word “association,” the post gave the impression that it was a study capable of establishing causality.

Despite attempts to stem the tide of misinformation and alarmism, the effort was insufficient. Major newspapers, such as O Globo, began to repost the material in a clickbait format, as in this case: “Most sweeteners are associated with up to 62% faster cognitive decline, shows an unprecedented study from USP.”

In fact, the impact was so great that even Agência SP – the official news production and distribution platform of the São Paulo Government – reproduced the finding, surprisingly also without highlighting that it was an observational study and, therefore, could only verify associations.

Unfortunately, the headline of an article is the first glimpse readers get of its content. If we headline an article something like “Dihydrogen Monoxide: Why Do We Continue to Sell a Substance Found in 100% of Recent Deaths?”, readers are likely to think they’re dealing with an extremely dangerous substance, when in fact it’s just pure water (H₂O).

Of course, in my ideal world, all readers would get past the article title and understand the context. However, as we know, most people don’t read the entire content and – even more tragically, this is true even whlen they share it. This creates almost a “snowball effect”: you see a friend or family member sharing a piece of news, believe they’ve read it, evaluated it, and found it relevant, and then you share it without reading it, expanding the reach of the information.

Given this, I believe we should address the article in its entirety and explain its actual findings and its limitations. However, before unpacking the USP findings, it’s vital to understand the study’s methodological basis: the Longitudinal Study of Adult Health – ELSA – which tracks health determinants and cognitive tests over time.

The ELSA

According to the article “Brazilian Longitudinal Study of Adult Health (ELSA-Brasil): Objectives and Design“, ELSA-Brasil is a cohort study involving 15,105 civil servants from six institutions in different regions of Brazil. In this type of study, a group of people are followed over time by researchers who seek to observe how certain “exposures” – to foods, pollutants, activities – relate to certain “outcomes” – such as health problems. Active or retired employees aged 35 to 74 were considered, excluding pregnant or recently pregnant women, individuals with severe cognitive or communication impairments, and retirees residing outside the metropolitan area of ​​the study centre.

The study aims to investigate the incidence and progression of diabetes and cardiovascular disease, considering biological, behavioural, environmental, psychological, social, and occupational factors. The first examination took place between 2008 and 2010, and the first follow-up between 2012 and 2013.

To establish a health baseline, participants underwent an initial interview about family history, dietary intake, social class, and social capital, as well as an electrocardiogram, anthropometric assessment, fasting blood collection, blood pressure measurement, and cognitive testing.

Three cognitive tests were applied: one on memory – word learning and retention – and two on executive functions, related to attention, concentration and psychomotor speed.

In the field of nutrition, the study “Reproducibility and relative validity of the ELSA-Brasil Food Frequency Questionnaire” evaluated the reliability and relative validity of the Food Frequency Questionnaire (FFQ). From a sample of 15,105 participants, 300 individuals were randomly selected (150 men and 150 women), distributed by age groups (35–54 and 55–74 years) and employee categories. For these participants, the FFQ was administered at the first contact (FFQ1, October 2009) and again in October 2010 (FFQ2). Three 24-hour dietary recalls were conducted, four months apart and between the two FFQs, for comparison of results.

To increase the accuracy of records, participants detailed all food and beverages consumed, using an album with life-size photos of utensils to estimate portions, as well as instructions on the days of the week and month to record.

The FFQ, consisting of 114 items, was semi-quantitative, assessing the frequency and average quantity of foods consumed in the last 12 months. Questions included sweetened beverages (“with sugar,” “with sweetener,” and “without sugar”) and eating habits, such as consumption of fast food and sweets. Each region included up to two local items, such as cuscuz paulista and Japanese food in São Paulo.

The final sample consisted of 281 participants (136 men and 145 women), with 54.8% between 35 and 54 years old and 45.2% between 55 and 74 years old. High variability in energy and nutrient intake was observed between FFQ1 and FFQ2, with lower averages in the second questionnaire, although carbohydrates, fibre, iron, potassium and zinc presented higher average values ​​in FFQ2.

The intraclass correlation coefficient – ICC – is an essential statistical measure in this context, as it assesses both consistency and absolute agreement between instruments, that is, whether the methods generated results very similar to each other. The ICC showed agreement of 0.55 (proteins) to 0.83 (vitamin E) between nutrients, being generally higher for micronutrients.

Average energy and macronutrient values ​​also varied: energy (ICC 0.51), proteins (0.38) and lipids (0.44). The percentage of agreement between the FFQ2 and food records ranged from 36.6% (fibre) to 48% (calcium), with an average disagreement of 13.5%.

In quantitative terms, the FFQ2 overestimated intake: on average, 783 kcal more for energy, 85 g for carbohydrates and 9.35 mg for iron, attributable to characteristics of the instrument, such as an extensive list of foods and the non-exclusion of extreme values.

Considering the ICCs found, it is concluded that the ELSA-Brasil FFQ presents reasonable relative validity to classify participants according to intake levels, allowing multiple dietary analyses.

One of the outcomes of ELSA-Brasil was the article “Examining the Usage Patterns of Non-Nutritive Sweeteners among Non-Diabetic Individuals: Insights from the Longitudinal Study of Adult Health (ELSA-Brasil)“, which estimated the prevalence of regular consumption of non-nutritive sweeteners – NNS – and their associated factors among non-diabetic individuals at the study’s baseline.

Exclusion criteria were applied: participants who did not respond to the food consumption section; underwent bariatric surgery; who reported dietary changes in the previous six months; presented implausible energy intake; or were diagnosed with diabetes mellitus or taking medication for the condition.

The final sample included 9,226 individuals, and regular NNS consumption was defined as ingestion of at least one NNS-sweetened product at least once per day.

The prevalence of regular NNS consumption was 27.5%, with coffee being the main source (20.9%). Regarding the sample characteristics, 39.2% were overweight, 64.5% had no family history of diabetes, 68.3% did not report prior hypertension, and 60.7% had higher education. Women had a higher prevalence of consumption (30.5%).

Regarding lifestyle, 80.3% reported alcohol consumption, 42.9% were smokers, and 78.3% had low levels of leisure-time physical activity. A progressive increase in the prevalence of NNS was observed with advancing age and higher BMI categories, in addition to a direct association with higher education level and per capita income. Other factors associated with consumption were: not being married, family history of diabetes, hypertension, and alcohol consumption.

In the adjusted exploratory analysis, women were almost twice as likely to consume alcohol as men, and white individuals were 50% more likely than black individuals. Participants aged 65 to 74 were 1.4 times more likely to consume alcohol than those aged 35 to 44, while obese individuals were 6.1 times more likely.

Having a family history of diabetes, systemic arterial hypertension, and alcohol consumption increased the likelihood of regular NNS consumption by about 20%, while moderate or intense levels of leisure-time physical activity increased the odds by 30%. Having higher education and an income above two minimum wages increased the likelihood of regular consumption by 80%, compared to the lowest income brackets.

Broadly speaking, this was the “theoretical basis” behind the study that generated so much controversy on social media. From the outset, some limitations can be identified.

These include: the fact that this is an observational study, which, due to its methodological nature, does not allow for the inference of causality, only correlation; the use of dietary assessment tools that, although fundamental in epidemiological investigations, are subject to significant biases, such as memory bias (given the difficulty of accurately recalling food consumption from previous days or months) and social desirability bias (responding in a socially acceptable way, such as underestimating the consumption of ultra-processed foods or overestimating the consumption of foods considered healthy); and the possibility of residual confounding variables, even after statistical adjustments, which may influence the findings.

With these considerations in mind, we can now move on to discussing the USP study.

Do sweeteners accelerate decline?

Published in the journal Neurology, the article “Association Between Consumption of Low and No-Calorie Artificial Sweeteners and Cognitive Decline” investigated the relationship between the consumption of seven low or no-calorie sweeteners – LNCS – and cognitive decline over eight years, based on the hypothesis that greater consumption would be associated with faster cognitive decline.

The ELSA-Brasil sample was evaluated at three time points (2008–2010, 2012–2014, and 2017–2019). At baseline, participants with incomplete data, extreme caloric intake, or a history of Parkinson’s disease were excluded, resulting in 12,772 individuals.

In subsequent measurements, losses occurred due to deaths, non-attendance, or missing data, totaling 5,784 and 10,707 participants evaluated, respectively. It is worth noting that, unlike the first two assessments, in which cognitive tests were administered only to participants over 55 years of age, the third assessment included all individuals.

The seven LNCS were identified from tabletop sweeteners and the composition of light and diet beverages. Based on this, combined consumption was calculated, and participants were categorised into tertiles, divided into three concentration groups: first tertile (0.02–37.2 mg), second tertile (37.3–102.3 mg), and third tertile (102.4–856.5 mg).

Furthermore, participants were classified according to the frequency of LNCS use into two categories: “no consumption/sporadic consumption (less than once a day)” and “daily consumption”.

Cognitive performance was assessed every four years. Episodic memory – responsible for receiving and storing information about specific episodes or temporal events – was measured using the Consortium to Establish a Registry for Alzheimer’s Disease word list, a battery of tests capable of assessing cognitive status and its changes, especially in older populations.

Semantic and phonemic verbal fluency tests were used to assess language and executive function – in which participants typically have one minute to produce as many words as possible from a given category or that begin with a specific letter.

Processing speed and executive function were assessed with version B of the Trail-Making Test.

The lifestyle and sociodemographic variables assessed were similar to those of other ELSA-Brasil studies, including BMI, diabetes, self-reported alcohol and tobacco consumption, and leisure-time physical activity. One difference was the classification of the diet as healthy or unhealthy, based on the MIND standard, which encourages green leafy vegetables, berries, and olive oil, and discourages fried foods, sweets, and red meat.

After eight years, participants in the highest consumption tertile were found to have a 32% greater rate of memory decline compared to those in the first tertile. Furthermore, compared to the first tertile, participants in the two highest tertiles had 110% and 173% greater rates of verbal fluency decline, respectively, and 35% and 62% greater declines in global cognition, corresponding to an excess cognitive aging of 1.3 to 1.6 years. Aspartame was associated with faster decline in memory, verbal fluency, and global cognition; acesulfame-K and erythritol affected memory and global cognition; tagatose had no significant effect.

When considering age, it was found that this factor modified the associations. Consumption in the highest tertile was associated with a faster decline in verbal fluency and global cognition in participants under 60 years of age. Interestingly, among participants aged 60 and over, no significant association was observed between tertiles of LNCS consumption and cognitive decline.

Stratifying by obesity, diabetes, and diet, only the presence of diabetes modified the relationship between total LNCS consumption and cognitive decline. In participants without diabetes, combined LNCS consumption in the highest tertiles was associated with a faster decline in verbal fluency and global cognition. In participants with diabetes, combined consumption in the highest tertiles was associated with accelerated decline in memory and global cognition.

Regarding individual sweeteners, in non-diabetics, erythritol and xylitol accelerated the decline in memory and global cognition, while sorbitol affected memory, verbal fluency, and global cognition. In diabetics, aspartame and acesulfame-K accelerated the decline in memory, verbal fluency, and global cognition; saccharin and xylitol affected memory and global cognition; and tagatose accelerated the decline in executive function.

Given these findings, the authors conclude that LNCS consumption was associated with an accelerated rate of cognitive decline during eight years of follow-up in this large cohort of middle-aged and older adults, suggesting the possibility of long-term detrimental effects of LNCS consumption, particularly artificial sweeteners and sugar alcohols, on cognitive function. Possible mechanisms that could explain these results include neurotoxicity, neuroinflammation induced by toxic metabolites of artificial sweeteners, and possible alterations in the gut microbiota.

Therefore, opting for more natural alternatives, such as tagatose, or other sugar alternatives may help mitigate the potentially harmful association observed. Future research is needed to confirm these findings and investigate whether other alternatives to refined sugar, such as honey, may be effective in this regard.

Among the limitations highlighted by the researchers, it is worth noting that long-term studies are subject to participant loss – as seen, since the first measurement, of the 15,105 individuals, only 3,857 completed all the cognition tests.

Furthermore, although a validated food frequency questionnaire was used, the possibility of reporting errors cannot be ruled out. Many covariates were self-reported, which may introduce social desirability bias.

Similarly, although regression models were adjusted for clinical and lifestyle variables, residual confounding cannot be excluded, particularly because health behaviours tend to co-occur, and some groups may consume more LNCS due to lifestyle and clinical history.

Personally, I find this quite plausible, and Figure 4 of the article supports this interpretation: the highest tertiles of total sweetener consumption – although they had minimal impacts in patients without diabetes – showed more significant associations with cognitive decline in patients with diabetes. This raises the possibility that the findings are not necessarily caused by the sweeteners, but rather by the disease itself when left untreated – something much more likely.

Another noteworthy aspect is the relationship between tagatose and cognitive decline in diabetic patients. Although this sweetener did not demonstrate statistically significant negative effects in most tests and even produced potentially neutral or beneficial effects on global cognition, the subsample of diabetic patients was associated with a more rapid decline in executive function. In theory, this contradicts the researchers’ conclusion that more natural options may be good alternatives to LNCS.

Furthermore, diet was assessed only at baseline, which may not reflect dietary changes over time and lead to an underestimation – or overestimation – of the associations between LNCS and cognition.

Finally, due to the unavailability of neuroimaging, it was not possible to investigate structural brain changes or potential mechanisms that explain the associations between LNCS consumption and cognitive decline in specific groups.

Ultimately, given the clear limitations, I can say that sweeteners – at least based on the evidence presented in this study and many others – remain safe. What’s concerning isn’t the metallic or bitter aftertaste some leave, but rather the fact that USP’s Instagram account didn’t take a strong stance and remove the alarmist language from the post.

References

• SUNDAR, S. et al. Sharing without clicking on news in social media. Nature Human Behaviour volume 9, pages156–168 (2025).
• AQUINO, E. et al. Brazilian Longitudinal Study of Adult Health (ELSA-Brasil): Objectives and Design. American Journal of Epidemiology 175(4):315-24. February 2022.
• MOLINA, M. et al. Reproducibility and relative validity of the ELSA-Brasil Food Frequency Questionnaire. Cad. Public Health 29 (2). Feb 2013.
• MOREIRA, T. Examining the Usage Patterns of Non-Nutritive Sweeteners among Non-Diabetic Individuals: Insights from the Longitudinal Study of Adult Health (ELSA-Brasil). Nutrients. 2023 Nov 15;15(22):4785.
• GONÇALVES, N. et al. Association Between Consumption of Low- and No-Calorie Artificial Sweeteners and Cognitive Decline: An 8-Year Prospective Study. Neurology. 2025 Oct 7;105(7):e214023.

This story was originally published by Revista Questão de Ciência in Brazil. It is translated and reprinted here with permission.

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For many, it will come as a surprise that denial of HIV’s role in causing AIDS could persist almost 50 years since the start of the AIDS epidemic. Sadly, Duesberg’s death does not herald the end of that misguided and dangerous movement: the Duesberg Hypothesis on AIDS lives on, in the shape of the world’s most popular podcaster – and repeated AIDS denier – Joe Rogan.

Joe Rogan and AIDS denial

In November 2025, Joe Rogan released episode 2,411 of his wildly successful podcast, The Joe Rogan Experience. In it, he spoke to security expert and self-styled vaccine researcher Gavin de Becker, and through a meandering three-hour conversation that has been viewed more than a million times on YouTube, the pair talked about Covid vaccines, swine flu, SIDS, autism, the tetanus vaccine, the polio vaccine, the measles vaccine, and the fact that Adolf Hitler didn’t really shoot himself.

Early in the conversation, Rogan raised the issue of AIDS, and his belief that HIV is merely a “passenger virus”, too weak to cause any harm to people – so weak that even newborn babies can fight off an HIV infection without any treatment (this isn’t true – there are babies who have tested positive on birth but negative later, but these were almost certainly the result of initial false positives). Instead, according to Rogan, people with AIDS-compromised immune systems were a result of the party lifestyle of the 1980s gay clubbing scene:

“The vast majority of the people that got air-quotes AIDS all were hardcore drug users. They were these partiers in the gay community… And these guys are burning it at both ends. And when you do that, sometimes you fucking die. Sometimes your immune system gets crashed”

While it’s true that participants in the 1980s gay party scene might have often had late nights and used recreational drugs, these were not the cause of AIDS – we know that, because there was no shortage of drug use among heterosexual clubbers in the 1980s, who experienced fewer cases of AIDS. Also, use of recreational drugs hasn’t gone away… but the widespread reality of AIDS as a death sentence has. The reason is clear: there was a virus circulating among sections of the population, which was eventually curtailed with effective treatments and then brought under control via a mixture of public health messaging and preventative pharmaceuticals.

Part of the reason HIV was able to circulate among the gay male community for so long was the stigma society placed on that community – stigma that Rogan explicitly perpetuated in his conversation with de Becker. Rogan repeated the myth that AIDS patients’ respiratory symptoms were caused by the prominent use of amyl nitrate, or poppers, in the gay community – in reality, the effects of HIV in decimating the immune system left AIDS patients susceptible to extreme infections by viruses that otherwise-healthy immune systems could fight off, including respiratory viruses.

Rogan even repeated the false notion that AIDS was a disease specific to the gay community:

“Why did it never make its way to the heterosexual community? If it’s really a sexually transmitted disease that’s so unbelievably contagious… how come it never really had any meaningful transition to the heterosexual community?”

The fact is, while AIDS did disproportionately affect gay men (HIV is more likely to spread through anal sex than via vaginal or oral sex), it is absolutely untrue that there was no transition to the heterosexual community. For one, the gay and heterosexual communities are not distinct; they’re not even sexually distinct. Men who have sex with men sometimes also have sex with women. In fact, according to AIDS Map from the Terrence Higgins Trust, 62% of new HIV diagnoses in the UK in 2024 came from heterosexual sex – outstripping the infection rate in men who have sex with men, partly because the heterosexual population is larger, but also because the message around the importance of safe sex has been received so effectively in the gay community.

Why did the world’s most popular podcaster believe these extraordinary – and comprehensively outdated – things? In 2012, Joe Rogan interviewed cancer researcher and prominent AIDS denier, Prof. Peter Duesberg.

Prof. Peter Duesberg

After finishing a PhD at the University of Frankfurt, Peter Duesberg was offered a position at the University of California, Berkeley in 1964, to study the role of viruses in the development of cancer. In 1971, he sequenced the genome of the Rous sarcoma virus (RSV), identifying a gene in the chicken virus that caused rapid, unchecked cell growth when inserted into the host genome. A gene called src (spoken as ‘sark’). This was the first oncogene to be discovered and was soon followed up by work from Duesberg’s colleagues, identifying an analogous src gene in human cells.

But Duesberg’s long-acknowledged contrarian streak saw him turn his back on his own discovery – a finding that had secured him international acclaim, and tenure at the age of 36 – in favour of a 1914 theory from German scientist Thodor Boveri.

Boveri had noticed that cancer cells contained an abnormal number of chromosomes, a trait called aneuploidy. This, Duesberg believed, was the true cause of cancer – rather than viruses, or genetic mutations. While it is true that most cancer cells exhibit aneuploidy, researchers have argued this comes as a consequence of cancer, rather than a cause – once a cell is affected by a virus or hit by a mutation, it can’t reproduce healthily and aneuploidy can result.

Duesberg didn’t just reject the role of viruses in causing cancer – he went further, stating that no retrovirus could cause harm to humans. According to Duesberg, retroviruses (whose genomes consist of RNA rather than the more common DNA template) have an evolutionary imperative to be harmless, “because they depend on viable cells for the replication of their RNA from viral DNA integrated into cellular DNA”. This belief would send him crashing headlong into the defining health crisis of the 1980s: the AIDS epidemic.

The AIDS epidemic

The first recorded AIDS patient in America was a teenager in St Louis in 1969, who developed Kaposi’s Sarcoma (KS) – a type of cancer that usually occurred in ageing men of Mediterranean ancestry, rather than young African-American men under the age of 20. At the time, doctors were confused as to how this came about, but retrospective tissue analysis has shown their condition was a result of having contracted HIV, which had caused AIDS.

KS became a common symptom among AIDS patients, with their compromised immune system leaving them unable to fight off the herpes simplex virus that can cause KS. However, prominent cancer specialist Professor Peter Duesberg disagreed with the hypothesis that a virus can cause cancer, or that any retrovirus can harm a human being. It was impossible, therefore, for HIV to be the root cause of AIDS.

In 1987, Duesberg wrote his now-notorious article in the journal Cancer Research, Retroviruses as Carcinogens and Pathogens: Expectations and Reality, where he explained that HIV is nothing but a “passenger virus” – the term explicitly used by Rogan, nearly 40 years later. According to Duesberg, HIV was present in AIDS patients only because their immune system was unable to defeat it, as the immune systems of healthy patients routinely did, and therefore the “AIDS virus could be just the most common occupational infection of those at risk for AIDS”.

The Duesberg Hypothesis

Given his unshakeable belief that HIV was a weak and inconsequential bystander in the human body, Duesberg had to find something that could account for the tens of thousands of people who were dying from AIDS. As such, the Duesberg Hypothesis was born, attributing the immune deficiencies of AIDS to the lifestyles of gay men in the 1980s – late nights, sexual promiscuity, recreational drugs, and regular use of poppers.

Obviously, the Duesberg Hypothesis couldn’t account for the large number of cases identified in Africa – which, in the 1980s, wasn’t as hospitable to the homosexual community as New York’s East Village. This wasn’t difficult for Duesberg – he explained that there is no AIDS in Africa, merely a case of the CDC and WHO “manufacturing contagious plagues out of noninfectious medical conditions”, such as malnutrition and unclean drinking water. This AIDS “myth”, he claimed, was egged on by the media in order to help secure funding for bogus AIDS initiatives, and supported by local doctors who were paid to keep up the pretence.

Rather than being dismissed, Duesberg’s ideas were taken up by other AIDS deniers of the time – including by Thabo Mbeki, who was South African president from 1999 to 2008. Mbeki appointed Duesberg as an advisor to lead their AIDS policy in 2000 and, as a result, an estimated 300,000 South Africans died.

Not that Duesberg accepted those figures. In 2009, he published an article in Medical Hypotheses, HIV-AIDS hypothesis out of touch with South African AIDS – A new perspective, denying that his advice had led to any deaths in South Africa, nor anywhere else. According to reviewers, the paper consisted of cherry-picked data alongside statements taken completely out of context.

After investigation, the journal retracted the article, but Berkeley took no further action and Duesberg remained a tenured professor – a position he held when he was interviewed by Joe Rogan for his podcast in 2012, in an episode that remains available on Spotify to this day. It would be a conversation that would set Rogan on the path to becoming an all-out AIDS-denier.

Joe Rogan and AZT

The evolution of Rogan’s AIDS denialism can best be tracked through mentions on his show of one further element of the Duesberg Hypothesis – one that Rogan clearly took to heart. At the height of the AIDS crisis, medical researchers worked hard to find a treatment that could mitigate the disease’s effects and prolong healthy lives. They soon settled on a little-known cancer treatment: zidovudine, or azidothymidine (AZT).

AZT had originally been developed in the 1960s as a treatment for cancer. The theory was that the drug would be able to insert itself into the DNA of a cancer cell and disrupt cell division as the cell tried to reproduce. Unfortunately, it proved ineffective: it simply wasn’t good at binding to cancer DNA. However, initial trials during the AIDS crisis showed that AZT was 100 times more effective at binding to an enzyme produced by HIV than it was to cancer cells’ DNA replication machinery and so the first antiretroviral medication to combat HIV was born.

However, if you were a regular listener to the Joe Rogan Experience, this is not the story you would be familiar with. During his interview with de Becker, Rogan claimed:

“AZT was a chemotherapy medication that they had to stop using because it was killing people quicker than the cancer was killing people… it had already been approved and they could just push them through quickly and they were very profitable.”

This is simply not true. There were no legions of cancer patients whose lives were cut short by AZT, because AZT never made it out of the lab and into hospitals. Where did Rogan get the notion that AZT had been deadly? It was a central pillar of the Duesberg Hypothesis. In his 1996 book “Inventing the AIDS Virus”, Duesberg described AZT as “dangerously toxic”. Duesberg’s evidence for this claim, as science writer Jonathan Jarry discovered when following up on citations, was a book from AIDS denialist Jon Lauritsen, who provided no evidence for the statement.

In their 2012 interview, Rogan and Duesberg talked extensively about the harms of AZT, though Rogan later admitted that the pushback the conversation received gave him pause for thought – reasoning that it might be unlikely that Duesberg is correct on this issue while every other professional in the field is wrong. As a result, he backed off discussions of AIDS, mentioning AZT in just four further interviews across the next seven years. It seemed like AIDS denial was an idea Rogan had flirted with, even entertained by having a prominent AIDS denier on the show. But between the backlash from his audience and the pushback from other guests, he’d reasoned his way either out of the belief, or out of expressing the belief in public – except when talking to someone who might also agree.

Then in 2021, something changed, and Joe began to raise the deadly nature of AZT with his guests more and more – on three shows in 2021, four shows in 2022, and seven shows in 2023. What sparked this renewed enthusiasm for a conspiracy theory from four decades prior?

Joe Rogan contracted Covid.

In 2021, Rogan posted a video on social media explaining that he’d tested positive for Covid, and that he was treating himself with a regime of ivermectin and supplementation. The pushback he received was global, with CNN featuring his video in their news bulletins. Rogan insists CNN applied a filter to the video in order to make him look sicker, and mocked him for taking ‘horse dewormer’. In reality, the video discolouration was far more likely a result of differences in image encoding between devices, with Apple devices rendering the HDR visuals in Rogan’s original post differently.

Regardless, the effect on Rogan was severe, hastening his radicalisation into more extreme health beliefs. In subsequent interviews, he explains that he’d managed to square the circle of his prior objection: is it possible that all of the other health professionals could be wrong about AIDS? Absolutely – after all, how many health professionals pushed the Covid vaccine, which Rogan was sure had been proven to be deadly, and how many of them mocked him for taking ivermectin?

Already firmly now radicalised along the road to health extremist, Rogan needed one final push to go all-in on AIDS denial… and in 2022 that push arrived in the form of a book: The Real Antony Fauci, by Robert F. Kennedy Jr.

Robert F. Kennedy Jr and AIDS

“The Real Anthony Fauci” is almost 480 pages long, with more than a fifth of those pages dedicated to resurrecting AIDS denialist arguments, including directly quoting the work of Peter Duesberg. Kennedy writes about the “orthodoxy that HIV alone causes AIDS”, and the “theology that HIV is the sole cause of AIDS”. He writes about how no one has isolated the HIV particle – echoing the ‘Koch’s Postulate’ argument that was also used by some to deny the reality of the SARS-CoV-2 virus that causes Covid.

The book accuses Dr Anthony Fauci – the public face of America’s Covid response – of having abused his power and position for 30 years, stretching back to the AIDS epidemic, when Fauci had been one of the country’s leading researchers. This was music to the ears of the world’s most popular podcaster, whose hatred of Fauci had been cemented in that backlash to Rogan’s use of ivermectin and his repeated scaremongering about the Covid vaccine. To Rogan, Fauci had masterminded the use of AZT on AIDS patients, in the full knowledge of how deadly the drug would be, in order to make money for pharmaceutical companies… pocketing a tidy profit for himself along the way.

The book had a colossal impact on Rogan – he has raised it in at least 30 different episodes, starting on Christmas Eve 2021 and spanning interviews with Bill Maher, Gavin de Becker, Aaron Rodgers, Russell Brand, Aseem Malhotra, and indeed RFK Jr himself. The book has become the new bible of AIDS denialism, penned by the man now in charge of America’s Health and Human Services.

It has also cemented Joe’s belief that, unequivocally, HIV is a weak virus that can’t harm people, but the drug companies came along and forced AZT onto people, killing them in the process, just to make money. And the doctors all agreed to cover that up in exactly the same way they all agreed to turn a blind eye to the many provable harms of the Covid vaccine; because it’s profitable for them to do so.

The resurgence of AIDS denial?

Joe Rogan is without question the most influential broadcaster in the modern alternative health ecosystem; Robert F. Kennedy Jr occupies one of the most powerful roles in the US healthcare system. Together, they hold outsized roles and influence on the health of Americans and people elsewhere, yet they are arm-in-arm bringing 1980s-era AIDS denialism back into the mainstream discourse. Worse still, these discussions happen at a time when the realities of the AIDS crisis are beyond the living memory of many in their audience.

This is a threat we should take seriously, just as we previously saw signs that the flat-Earth movement we once thought dead and buried could return with renewed vigour, and just as the antivax movement we thought had ended in the 2010s came back with a vengeance in the 2020s.

Peter Duesberg’s life saw him responsible for the deaths of hundreds of thousands of people, given the respected position of influence he had achieved and the political connections it afforded him. He might be dead, but his legacy more than lives on in RFK Jr and Joe Rogan.

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The BBC’s account of the case is devastating. Kate Shemirani even sent messages in all caps to Paloma’s boyfriend: “TELL PALOMA NOT TO SIGN OR VERBALLY CONSENT TO CHEMO OR ANY TREATMENT.” Hospital staff wrote down their “concern about maternal influence” on the patient, but acknowledged that Paloma had the legal capacity to make her own decisions. A young woman who was gradually convinced that the medicine that could save her was, in fact, her enemy.

This case tragically illustrates a phenomenon I observe frequently. With almost weekly regularity, I encounter comments like “the pharmaceutical industry doesn’t want a cure for cancer to be found” or, even more dramatically, “they even kill those who find the cure”.

These statements are, to some extent, understandable because they stem from a collective distrust of large corporations. The problem is that this almost-skeptical stance ends up being manipulated and directed to fuel misinformation about how medical science works.

What the data shows

To understand the true scale of the problem, we can examine a study published in the journal JAMA Oncology in 2018. Researchers analysed data from nearly 2 million patients diagnosed with curable cancers (breast, prostate, lung, and colon) in the United States between 2004 and 2013, from more than 1,500 accredited cancer treatment centers. They used a methodology that adjusted for variables such as age, clinical stage, comorbidities, insurance type, ethnicity, and cancer type.

In the sample studied, they identified 258 patients who used complementary medicine, specifically defined as “unproven treatments administered by non-medical personnel”, in addition to conventional treatment. This seemingly small number actually reflects the difficulty of documenting the use of these practices, as many patients do not disclose to their physicians that they are using alternative therapies and, when they do, it is not always documented in their medical records.

The results are worrying. Patients who opted for complementary medicine had higher rates of refusal of conventional treatments: 7% refused surgery (compared to only 0.1% of the control group), 34.1% refused chemotherapy (compared to 3.2%), 53% refused radiotherapy (compared to 2.3%), and 33.7% refused hormone therapy (compared to 2.8%).

Most importantly, 5-year survival was 82.2% in the group using complementary medicine, compared to 86.6% in the control group, an absolute difference of 4.4% that, although it may seem modest, represents thousands of preventable deaths when extrapolated to the general population, considering the approximately 700,000 new cases of cancer diagnosed annually in Brazil.

The difference in mortality disappeared when researchers adjusted the data to account for refusal of conventional treatments. In other words, it is not the complementary intervention itself that appears to increase mortality, but rather the systematic tendency of users to refuse treatments with scientifically proven efficacy.

Another interesting aspect of the study was the demographic profile of “complementary medicine” users. Patients who opted for these therapies were, on average, younger, more educated, had better access to private health insurance, and had a higher median family income. A profile similar to that of Paloma Shemirani.

Conspiracy ideas

Let’s return to the phrase I hear almost weekly: “The pharmaceutical industry doesn’t want a cure for cancer to be found”. While it sounds shocking, it ignores the fact that:

1. Many cancers are already cured

Several types of cancer currently have high cure rates. Breast cancer, detected early, has a survival rate of over 90%. Childhood leukemia, which was practically a death sentence just a few decades ago, now has cure rates above 80%. Thyroid cancer has a 5-year survival rate of over 98%. Testicular tumors, even when metastatic (having spread from the original site), have a remission rate of over 90% in cases with a good prognosis. Melanomas detected early have a 99% survival rate.

If there really were a corporate conspiracy to hide cures and keep patients sick indefinitely, how would we explain these widely documented, celebrated, and publicised advances? Is it a curiously incompetent conspiracy, systematically “forgetting” to suppress successes in certain areas while obsessively focusing on others?

Or perhaps it’s simply the naturally uneven and progressive scientific development that characterises all medical research. Some problems are easier to solve than others, some organs are more surgically accessible, some tumors respond better to chemotherapy. It’s biological reality being confused with conspiracy.

2. “Cancer” is not just one disease

Herein lies perhaps the greatest conceptual error fuelling conspiracy theories: the idea that ‘cancer’ exists as a single entity. In reality, the term encompasses more than 200 molecularly distinct diseases, each with its own genetic, behavioural, and therapeutic characteristics, differences amplified by the particularities of each individual’s immune system.

Lung adenocarcinoma is as different from acute lymphoblastic leukemia as the flu is from malaria. Both are ‘diseases’, but their mechanisms, treatments, and prognoses have almost nothing in common. Searching for a “universal cure” for cancer is like searching for a single medicine that simultaneously cures the flu, tuberculosis, malaria, meningitis, AIDS, and syphilis.

3. The economic paradox

Here we encounter a fundamental economic paradox. A company that developed a ‘guaranteed and effective’ cure for just one of the most common cancers would automatically become one of the most valuable corporations in history. The global oncology market is indeed worth billions of dollars annually. A company holding the patent for a revolutionary cure for, say, lung cancer, could charge virtually any price and still have guaranteed global demand.

Why would a corporation voluntarily give up the largest profit in the history of medicine? Conspiracy logic would require all the world’s major pharmaceutical companies –companies that compete fiercely for market share, sue each other for patent infringement, and engage in industrial espionage – to maintain an unbreakable secret pact to forgo trillions of dollars in profits.

4. Who profits from the conspiracy?

Those who profit most from the systematic distrust of conventional medicine are the sellers of “alternative cures.” Kate Shemirani’s case is a perfect case study of what I previously called the Chameleon Lobby: the strategy of using criticism of corporations to shield one’s own questionable business practices.

Kate charges £70 for annual memberships on her website and £195 for individual consultations, selling everything from apricot seeds with “potential health benefits” to personalised 12-week programmes for cancer patients.

The global alternative medicine market also generates billions of dollars annually, growing at rates exceeding 20%. Unproven treatments, “miracle” supplements, pseudoscientific therapies, and “superfoods” thrive because they don’t need to demonstrate efficacy or safety through rigorous studies. It’s a market that operates with stratospheric profit margins (after all, how much does it cost to produce a bottle of “energised water” or a juice-based “detox” program)?

5. Persistence of aggressive treatments

But why, then, do doctors sometimes insist on chemotherapy, even in very advanced cases with bleak prognoses? Why do they continue to offer “another line of treatment” when the chances of benefit are statistically minimal? Is it because they’re serving the industry?

The answer lies in the complex intersection between our collective cultural difficulty in accepting the finitude of life, the still incipient evolution of palliative care in Brazil, and the psychological pressures inherent in medical practice. It is, in fact, a human limitation that reflects the cultural relationship with death. Health professionals are trained to heal, to intervene, to ‘do something‘. The idea that sometimes the best medicine is to not medicate goes against decades of conditioning.

Patients and families, in turn, tend to interpret the lack of active treatment as ‘giving up’ or ‘abandonment’. There is enormous social and emotional pressure to ‘fight to the end’, even when that fight becomes a prolongation of death, not life. This reflects what we’ve already discussed about heroic medicine: the psychological pressure to act, even when the best course of action would be to accept that we’ve reached the limits of what medicine can offer.

6. A real question

There’s a documented and growing problem in modern oncology that deserves serious discussion: overdiagnosis. Increasingly sensitive tests detect cellular changes that technically fall under the definition of ‘cancer’, but would never cause significant clinical problems if left untreated.

These indolent lesions end up being treated as ‘real’ cancer, subjecting patients to invasive procedures, anxiety, costs, and side effects to treat irrelevant diseases.

This is especially true of poorly designed screening programs and the growing epidemic of unnecessary checkups (a phenomenon we already addressed when discussing quaternary prevention). Paradoxically, some of today’s oncology ‘successes’ may reflect this ability to detect and treat cancers that never needed treatment, rather than actual advances in curing clinically significant cancers.

But it’s important to note: this is a real problem that the medical community recognises and is working to correct. And how? Not through conspiracy, suppression of information, or denial, but through open scientific research, transparent discussion of the medical literature, guideline revisions, and continuing professional education.

Final considerations

Cancer conspiracy theories often urge the public to ‘research for themselves’ and ‘question everything’, but they rarely present evidence that stands up to rigorous scientific scrutiny. When specifically questioned about biological mechanisms, statistical methodologies, peer review, or replicability of results, the claims invariably turn out to be based on biased testimony, conceptual misunderstandings, or deliberately fabricated misinformation.

It is a form of performative skepticism: it uses the language and values ​​of legitimate scientific inquiry but selectively, applying asymmetric standards of evidence that require extraordinary evidence for conventional claims and accept minimal evidence for extraordinary claims.

Oncology medicine faces real limitations that deserve honest discussion and constructive criticism: costs that make treatments inaccessible to millions of people, side effects that can be physically and emotionally devastating, protocols that sometimes prolong suffering unnecessarily, unequal access based on geography and class, conflicts of interest in research, overdiagnosis, etc.

These are complex and important issues that can be resolved with more high-quality science, transparent research, public investment in palliative care, more equitable health policies, and rigorous health regulations. These are problems that require sophisticated, evidence-based solutions implemented through transparent, democratic processes. And they definitely cannot be resolved with conspiracy theories that ultimately enrich modern-day crooks and kill people like Paloma Shemirani.

This story was originally published by Revista Questão de Ciência in Brazil. It is translated and reprinted here with permission.

The post The high price of anti-science paranoia and fake cancer-cure conspiracies appeared first on The Skeptic.

The most interesting thing came later: as the original participants were gradually replaced by new volunteers, the “inherited” responses of the initial group continued to be perpetuated for generations, even when no one knew why those specific values ​​had been chosen. An arbitrary tradition had crystallised into “collective knowledge.”

This experiment, although conducted in a controlled environment, reflects a phenomenon that permeates the health field: the persistence of practices whose origins are purely arbitrary, but which stubbornly resist scientific scrutiny and evidence-based change.

What counts as arbitrary in the healthcare context is not simply a question of questionable origins (many scientific discoveries arose from accidents or initial intuitions). A practice can be considered arbitrary when its origin is based on cultural conventions, personal preferences, or administrative decisions without scientific basis; it remains unchanged for decades despite the availability of evidence suggesting superior alternatives; and its maintenance is due more to institutional inertia than to empirical validation.

Calendar-Based Medicine?

Consider this example: why are antibiotic cycles multiples of seven days long? Cystitis, seven days. Cellulitis, 14. Prostatitis, 28. The answer is as simple as it is arbitrary. In the year 321 CE, the Roman emperor Constantine decreed that Sunday would be a day of rest for the urban population, cementing the seven-day week, which at the time coexisted with other cycles, such as the eight-day week, in Roman law.

While the standard year has 365 days because it roughly reflects the time of Earth’s orbit, and the day has nearly 24 hours due to the planet’s rotation period, the duration of antibiotic treatments essentially follows a decision similar to that of a Roman emperor (the cultural adoption of the number seven follows no biological criteria). It’s an irony that should shame us: one of the most fundamental practices of modern medicine is anchored more in Constantine’s calendar than in pharmacological science.

PSA (prostate-specific antigen) offers another example. The 4ng/ml cut-off value, used worldwide to decide on prostate biopsies, was established arbitrarily, without any basis in robust clinical studies. Today, we know that approximately 15% of men with a PSA below that cut-off will have prostate cancer, and that the very amount of samples collected during the biopsy (also defined arbitrarily) directly influences the likelihood of finding tumours.

Similarly, the recommendation to operate on hydroceles (accumulation of fluid in the scrotum) after two years of age is based on a convention without solid foundation. Why two years, and not 18 months or three years? Another decision that crystallised without adequate scientific reflection. The same can be said about routine episiotomy, which we discuss in this text.

Psychology of perpetuation

The persistence of these arbitrary practices cannot be explained solely by a lack of access to information or individual resistance to change. It is a more complex and systematic phenomenon, which so-called behavioural economics helps to unravel through concepts such as the status quo bias, the power of inertia, and the default effect.

The status quo bias reflects our natural preference for the current state of affairs. In medicine, this manifests itself when protocols are followed simply because ‘it’s always been that way’, a behaviour often reinforced by classic arguments of appeal to tradition (‘we’ve always done it this way’) and appeal to popularity (‘everyone does it this way’). Questioning the established order requires cognitive energy and professional courage that many prefer to economise on.

The power of inertia amplifies the phenomenon. Just as subscription companies default to automatic renewal, knowing that most customers won’t revisit the decision, medical protocols, once established, are rarely critically re-evaluated. A study of the Swedish pension system showed that 73% of people who opted for the default investment choice didn’t revisit their decision for 16 consecutive years, even when their retirement depended on it.

The default effect completes the trio: the tendency to accept preselected options without question. In the traditional medical hierarchy, this is amplified by the vertical transmission of knowledge, in which protocols pass from teacher to student with little or no questioning of their origins or foundations.

The availability heuristic adds an extra layer of complexity. This cognitive bias causes professionals to base judgments on how easily they can recall past experiences, rather than considering broader probabilistic evidence. In healthcare practices, this manifests itself when a professional maintains a specific practice because they ‘remember cases where it worked’ or avoids changes because they ‘have seen it fail’.

When an arbitrary practice becomes routine, the ‘success’ cases associated with it become easier to remember, creating a false perception of effectiveness. Simultaneously, due to loss aversion (the tendency to value what we lose more than what we gain), negative outcomes associated with protocol changes become remembered as examples that discourage future innovation.

Thus, a vicious cycle is formed: arbitrary practices generate selective memories that ‘validate’ them, while attempts at change are discouraged by amplified memories of potential problems. Tradition perpetuates itself not because it is effective, but because we are programmed to preserve the familiar and fear the unknown.

Structural arbitrariness

Traditional medical education functions as a perpetuation machine for these practices. By emphasising memorisation and repetition of protocols, it inadvertently creates professionals less inclined to critical questioning. The time pressure of clinical decisions reinforces this dynamic: reviewing established procedures demands time that is rarely available in everyday practice.

Legal liability reinforces resistance. Deviating from widely accepted practices can be seen as a legal risk, even when new evidence suggests superior alternatives. The result is a system that punishes evidence-based innovation while protecting conformity to traditions, even if unfounded.

Paradoxically, healthcare professionals who follow arbitrary protocols are legally more protected than those who apply the best available evidence if it diverges from ‘common sense in health’. It’s a reversal of values ​​that transforms up-to-date scientific knowledge into a professional risk factor.

Returning to the example of antibiotic use, we often encounter the belief that one should always ‘complete the cycle’ (the one based on Constantine’s weeks). Two justifications are routinely invoked: avoiding relapses and preventing bacterial resistance. The problem is that there is no solid scientific evidence to support either assertion. On the contrary: recent studies suggest that excessive duration of antibiotic treatments may be more harmful than beneficial, contributing to bacterial resistance and unnecessary adverse effects. But the belief in the ‘complete cycle’ is so ingrained in medical culture that questioning the practice still generates discomfort and resistance.

This doesn’t mean that, as patients, we can stop taking antibiotics on our own at any time. It’s crucial to clarify: the debate over treatment duration concerns the formulation of protocols by professionals and researchers, not individual patient decisions. What we’re questioning here is not whether patients should comply with their prescriptions, but whether the protocols guiding those prescriptions are based on the best available scientific evidence.

Final considerations

The Behavioral Economics models presented here were primarily described for contexts where the consequences are financial, while in the healthcare field, the consequences involve illness and death. It is important to consider that this difference can significantly alter the manifestation of cognitive biases.

Medical practice has unique characteristics (responsibility for human life, strong regulation, logistical complexity) that foster resistance to change that transcends individual biases. Therefore, not all persistence of arbitrary practices can be explained solely by behavioural factors; resource constraints, legitimate scientific uncertainties, and systemic pressures also contribute.

Understanding these psychological and systemic mechanisms should not generate pessimism, but rather foster more sophisticated strategies for transforming healthcare practices. Recognising that resistance to change is not just a matter of ‘education’ or ‘access to information’, but a complex behavioral phenomenon, can guide more effective approaches. The implementation of Evidence-Based Medicine fails not only due to a lack of evidence per se, but also due to a failure to adequately consider psychological and structural obstacles.

Perhaps by better understanding the mechanisms that sustain unfounded practices, we can free medicine from the tyranny of its own traditions, building a practice genuinely based on evidence, critical questioning, and real benefits for patients.

This story was originally published by Revista Questão de Ciência in Brazil. It is translated and reprinted here with permission.

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Personally, I think Veganuary is a terrible idea, but not because I’m against reducing our meat and dairy intake – far from it. We know the environmental impact of eating meat and consuming milk-based produce is high, so anything we can do to reduce our intake even by a little is going to have an appreciable effect on the carbon emissions associated with our food. But January is a terrible month to take on a large-scale adjustment to your diet. January is cold and dark and miserable, and the last thing you should be doing is finding ways to make it even more cold and dark and miserable by limiting one of the few things you can control in January that can bring you some joy: what you eat and what you drink.

Nevertheless, for a lot of people January is the month when they make ambitious changes to their diet, including switching out their milk for non-dairy alternatives. However, according to recent studies, that might be very bad for them. The Telegraph proclaimed on 5 January: “Vegans are more likely to be depressed, study suggests”, while Women’sHealth went with “New research says drinking plant-based milk ‘increases risk of depression’”, and the Daily Mail coverage was headlined: “Experts issue warning over oat milk – dairy alternative linked to health harm while semi-skimmed cow’s milk boasts surprising benefit”. Here’s a flavour of what the Mail had to say:

If you splash almond milk over your porridge or opt for oat milk flat whites, then you might want to think again. Opting for plant-based diary alternatives could harm your mental health, if new research is to be believed. 

Scientists, who tracked more than 350,000 Brits, discovered plant-based milk drinkers were more likely to suffer from depression than those who drank semi-skimmed cow’s milk. 

These headlines reported on a study published in Frontiers in Nutrition, in which, as the Daily Mail explained, scientists at Southern Medical University in Guangzhou in southern China tracked the diets and mental health of 350,000 British people, collected as part of the UK Biobank study. The UK Biobank is a long-term study in which half a million people aged 40–69 were recruited between 2006 and 2010, consenting to have their anonymised biological samples, health-related data and lifestyle questionnaire data made available to researchers. Since then, these records have been periodically updated with cognitive tests and follow-up questionnaires, some of which track changes in mental health, and it’s that long-term comparative data that these Chinese researchers were interrogating.

According to the paper, the researchers examined the reported milk consumption habits of 502,402 UK BioBank participants. In the initial intake questionnaire, participants were asked “What type of milk do you mainly use?”, and were provided with a list of options: full cream, semi-skimmed, skimmed, soya, other types of milk, never/rarely consume milk, do not know, and prefer not to answer.

The researchers omitted from the study those who didn’t know or didn’t answer, and then lumped the soya milk respondents in with ‘other milk’.

They then looked at the reported mental health scores for these participants, which were assessed on initial intake using a questionnaire that consisted of four questions – two regarding depression, two for anxiety. Participants rated their thoughts and feelings over the past two weeks on a scale of 0 (not at all) to 3 (nearly every day), and if they scored full marks on both relevant questions, they were judged to have depression or anxiety, or both.

The researchers omitted the 52,306 participants who didn’t answer the mental health questions on intake, and the 1,149 who never responded during the later follow-ups. Finally, they omitted any participant whose results indicated they had depression or anxiety on initial intake – 89,852 people.

This left them with 357,568 participants, of which around 23,125 were full-cream drinkers, 232,878 were semi-skimmed drinkers, 72,342 drank skimmed milk, 17,583 drank ‘other’ milk (including the soya drinkers), and 11,640 did not consume milk. Then they looked at the follow-up depression and anxiety scores across the various types of milk consumption, comparing them to the non-consumers as a baseline. What they found was summarised in the Mail as:

semi-skimmed cow’s milk drinkers were 12 per cent less likely to be depressed and 10 per cent less likely to have anxiety. Those who consumed plant-based milks, such as soya and almond, had a 14 per cent increased chance of depression.

The Daily Mail included some of the researchers hypothesised reasons for these findings:

semi-skimmed contains more good fats than skimmed milk but fewer bad fats than full-fat. Previous research has found ‘good fats’ may increase the production of serotonin — a hormone that can alter mood. This, they theorised, means the milk could sit in a sweet spot where it improves mental health. It also shatters the myth that milk alternatives are always the healthier option, they argued. 

Except, that’s not true, because “shattering the myth of milk alternatives” is not something that is argued in the paper. This paper says nothing at all about the dangers of drinking non-dairy alternatives to milk – and there is zero mention of oat or almond milk in the entire paper. It seems that the Mail made that bit up (or, perhaps, cribbed it from a press release that invented it), and then added “they argued” to the end in order to put these thoughts into the mouths of the researchers. In reality, all of the findings in the study focus on the positive health benefits of semi-skimmed milk over all other types of milk in the study:

‘Milk is a rich source of nutrients such as lactose, lipids, protein and minerals, which are essential for maintaining human health…

Among the three milk types, full cream milk contains higher levels of saturated fatty acids, while semi-skimmed milk offers a moderately reduced amount. Excessive intake of saturated fats is associated with elevated levels of circulating saturated long-chain fatty acids, such as palmitate, which are positively correlated with the severity of depression…

The fatty acid profile of semi-skimmed milk might provide greater cerebral protection compared to full cream milk and skimmed milk, thereby potentially reducing the risk of both depression and anxiety…

These findings suggest that semi-skimmed milk may have a protective effect against these mental health conditions, presenting new prospects for dietary interventions.

What can we make of all of this? Firstly, it’s worth noting a minor point: the researchers from the Southern Medical University in Guangzhou were from, specifically, the School of Traditional Chinese Medicine at that university. That’s not to say that makes them bad researchers, or that we should ignore their results, but it is context that would be remiss to leave out. If they were from the homeopathy department of a British university, we’d expect that to be made clear. Traditional Chinese Medicine is a little different to homeopathy at least politically, in that there are departments of TCM at major Chinese universities and it receives more legitimacy and funding than it ought to, so likely attracts researchers who are drawn more by the resources than the ideology, but nevertheless it is worth noting.

Now let’s turn to those headlines. Neither The Telegraph’s “Vegans are more likely to be depressed, study suggests”, nor Women’sHealth’s “New research says drinking plant-based milk ‘increases risk of depression’” accurately reflect this study, as researchers were looking to compare semi-skimmed milk to other types of milk – they weren’t looking at vegan alternatives to milk. Worse still is the Daily Mail’s headline, “Experts issue warning over oat milk” – we can confidently dismiss that, because this study at no point mentions oat milk, not even once. That shouldn’t be a surprise, because the dataset it interrogates did not ask people how much oat milk they drank. They provided the options ‘soya milk’, and ’other types of milk’.

This makes sense, because back in 2006 when the UK BioBank started recruiting people aged 40-69, oat milk wasn’t a particularly common or readily available alternative to milk. Statistics on this are hard to find, but I was able to track down a February 2019 BBC article on the comparative popularities of vegan milks, which showed oat milk made up less than 5% of searches for vegan milk alternatives as far back as 2012, according to Google Trends, with soya milk and almond milk leading the market since. That 2019 article even notes that oat milk companies only recently entered the UK market. That aligns with Mintel market research reports from the time, surveying consumers’ milk choices – soya milk made the list of options, but oat milk wasn’t even included. By 2014, oat milk made up less than 1% of purchases. Suffice to say, oat milk wasn’t common when these people were asked which milk they were drinking in 2006 to 2010. And it’s the only time any of these people were asked what they were drinking – they were not asked again in 2022 when asked for their updated depression and anxiety scores.

Even the initial milk intake of the participants is less than reliable – it was self-reported data, which is prone to messiness. Take me, for example: currently, I mostly drink soya milk, unless when I’m at someone else’s house or I’m out, in which case I drink semi-skimmed. But also, if I’m looking for something to buy and drink as I’m on the go, I’m more likely to buy a pint of milk to drink than a bottle of coke, and if I do that it’d be semi-skimmed or possibly even whole milk. What would I respond to “do you drink milk?”.

Given that the data was self-reported, we don’t even know how much milk each participant consumed. That is a significant issue, if the working theory is that fats in semi-skimmed milk offer some protection against mental health issues. Several people in my life are regular semi-skimmed drinkers, but their milk consumption amounts to half a teaspoon of milk in a cup of tea several times a day – perhaps half a pint of milk per week. Meanwhile, I eat cereal every morning, and have a generous glug of soya milk in each cup tea I drink. Comparing type of milk without noting quantity is comparing apples to oranges, from a nutritional perspective.

Additionally, in 2006-10 during the initial UK BioBank questionnaires, it isn’t just that there was less oat milk around for people to self-report drinking – there were fewer non-dairy alternatives in general. The category of ‘non-dairy’ milk or ‘milk alternative’ was so uncommon that many people wouldn’t have been able to explain what it meant. That’s actually not a problem for the study, because the UK BioBank didn’t ask what ‘non-dairy’ milks people drank – they only asked whether they drank full-cream, semi-skimmed, skimmed, soya, or ‘other’. Anything that wasn’t one of the four stated categories was bundled into the ‘other’ category – yet it’s that ‘other’ that has been translated to ‘non-dairy alternative’ (or even just ‘oat milk’ in the reporting).

Significantly, ‘other’ is not a synonym for ‘non-dairy’: it would include, for example, gold top – a high-fat premium milk that was readily available from milk delivery services (certainly more so than soya milk or oat milk). It might mean reduced-fat milk that’s not quite semi-skimmed. It might mean lactose-free milk. It might mean organic milk, goat milk, or sheep milk. ‘Other’ might include people who didn’t realise ‘whole milk’ was a synonym for ‘full-cream milk’. It might include people who drink UHT milk but thought it was it’s own category. There’re lots of reasons why that ‘other milk’ category may include a large number of dairy-milk drinkers and it isn’t as synonymous with milk alternatives as it is portrayed in the reporting.

All of that is just an issue with the reporting, because the paper itself doesn’t look at how bad vegan milk is: it looks at whether semi-skimmed is superior to everything else. That focus might well explain why the researchers took the one piece of non-dairy information they did have – the soya milk data – and rolled it into the ‘other’ category. Cow’s milk gets broken down by three different levels of fat content, but the researchers pollute the only unambiguously non-dairy data they have, because they weren’t comparing non-dairy to dairy, they were looking at which level of fat content in milk was best.

That’s not to say that the researchers did nothing unusual in their analysis. They omitted the nearly 90,000 participants with depression or anxiety in the original baseline measurements, which is not ideal, given they were looking at levels of anxiety and depression in the population. By removing the people who had depression to begin with, they may argue they were left with only the participants who developed depression during the course of the study, but the omission effectively skewed their baseline, leaving them with a cohort of participants who were now artificially above the background level of depression and anxiety in the population.

What the study does not have, because it was removed from the dataset before any analysis, is how many people at baseline had depression, and what types of milk they typically consumed. What if that data found an existing depression or anxiety skew towards one particular type of milk? That might have indicated that people who have depression or anxiety have characteristics that also influence their consumption choices.

The demographics of the various milk consumption options are also distinct in a way that does not appear to be random. For example: women made up 50% of semi-skimmed drinkers, 61% of skimmed and 67% of the ‘other milk’ category, but just 37% of full-cream. Smoking rates are just as stark: just 5.9% of ‘other milk’ drinkers were smokers on initial intake – the lowest of any group, followed by 6.2% of skimmed milk… but a full 18% of full cream drinkers were smokers at the time of the initial data collection.

‘Other milk’ drinkers were more likely to exercise (61% compared to 55%-56% for the remaining categories). ‘Other milk’ drinkers ate more vegetables and fruit than all but the milk non-consumers – not by a lot, but consistently. 37% of ‘other milk’ consumers did not drink alcohol, compared to 31.5% full, 25.6% semi, 28.6% skimmed, and 27.2% milk non-consumers. ‘Other milk’ drinkers had the lowest rates of diabetes – 3.6%, compared to 3.9% full, 4.9% semi, 5.1% skim and 4.8% non-consumers.

Clearly, from the demographic breakdown, people who were more health conscious – who smoked less, drank less, and ate more fruit and vegetables – were more likely to drink this ‘other’ category of milk. This feels significant: perhaps the same factors that lead someone to be more conscious of their health are the factors that might lead them to experience depression or anxiety 15 years down the line.

The fact that those second measurements of anxiety and depression took place almost 15 years after the initial readings is also important. First, it means that the intake who were 40-69 at the time of first reading were 55-84 at the second measurement of their anxiety and depression. Obviously, along the way, 1,149 patients were ‘lost to follow up’ – given the upper end of that age bracket, we can imagine what ‘lost’ might mean for a lot of them. That itself might also introduce a bias into the data: how many of the hard-drinking, hard-smoking, non-exercising, whole-milk-drinking participants didn’t make it to their 80-somethingth birthday to tell us about their depression?

The paper does specify that they performed subgroup analyses on these demographic variances, and that they showed no statistical significance. Though obviously they were focused on semi-skimmed milk, as that’s what the study was really about – it wasn’t about other milk or oat milk at all.

The 15-year gap to follow-up introduces another confounding issue: how many of the participants had, at some point during the intervening 15 years, changed their milk preferences – either from dairy to other, or even just from full-cream milk to semi-skimmed milk? We don’t know, because the data doesn’t include that, despite the huge boom in awareness of and interest in dairy alternatives since 2010. There’s no way of measuring whether any of the people in one category of milk consumption are even still in that category now.

A further thing that is hard to rule out is that many people would argue that world events include some clear causes of anxiety and depression, even in 2022 when the follow-up measures took place. It may well be the case that that people whose demographic data put them in the more health conscious, non-smoking, low-drinking categories, might also be the kind of people who pay more attention to anxiety-inducing global events. Or, perhaps, that people who made climate-conscious choices about their diets in 2010 had feelings of anxiety and depression in 2022… as the world continues to do too little about the climate crisis. There is no distinction in the paper between clinical anxiety and reasonable concern about the catastrophic nature of current events. It could be that this study filters for awareness.

Ultimately, despite the headlines, this study never had anything to say about oat milk, nor any non-dairy milk. It suggests that consuming semi-skimmed milk is associated with lower levels of depression and anxiety than ‘other’ types of milk, but it does that observationally, where it can only point out associations and not causes. It speculates as to a nutritional reason for this, but that’s all it is: speculation, because even the milk consumption was self-reported. The study even notes that it doesn’t have access to dietary information or total energy intake, which could be confounding factors.

All in all, it is probably fine to stick with your vegan alternatives to milk – there’s no good evidence that they’ll cause you anxiety, and they’re certainly better for the environment. Just take my advice and don’t go making any major dietary changes in the darkness of January and February, because winter is already depressing enough.

The post No, a study didn’t show oat milk and veganism will make you depressed appeared first on The Skeptic.

There are a few questions I can usually guarantee will come up during the Q&A, one of which is around the idea that cancer often has an environmental cause – someone will reliably ask me is cancer sometimes preventable, and if that is the case, what can I recommend doing to avoid cancer.

This is not a simple question to answer.

Firstly, cancer while cancer can be caused by environmental factors, it is not only caused by environmental factors. It can also be caused by heritable genetic factors. In adult cancers this typically means you’ve inherited a predisposition to a particular cancer, like changes in the BRCA gene which increases your risk of breast cancer. Inheriting those genetic changes does not mean you’re guaranteed to get cancer, but it increases the likelihood that you will develop cancer in your lifetime.

In some cases, you might be able to do something to change your risk levels – such as a complete double mastectomy to remove all breast tissue, if you are carrying certain BRCA mutations. But it many cases you are unlikely to know which genetic mutations you carry, and even if you do know, there’s not much you can do to reduce your risk, beyond reducing the environmental factors which might exacerbate your risk. For example, if you know you’re genetically predisposed to colorectal cancer, then you might reduce your exposure to certain foods, or you might undertake more regular screening.

Secondly, cancer is a disease of living. The longer you live, the more likely you are to get cancer. While this is partially to do with lifetime exposure to environmental factors that can increase your risk of cancer, it’s also just the nature of living. If each cell replication has a certain percentage risk of leading to a genetic mutation, then the more cell replications, the more genetic mutations you will acquire. And if each genetic mutation has a certain percentage risk of being cancer causing, then the more genetic mutations you acquire, the more likely you are to acquire a cancer-causing mutation.

These are things we have little to no control over. However, the thing we do have control over, to some extent, is our environment. We know that exposure to some environmental factors increases our risk of acquiring a genetic mutation. The examples I usually give – partly because we’re so clear on the connection – are alcohol, sunshine and smoking tobacco.

Cutting out smoking is a no-brainer. It absolutely causes cancer, and it is the biggest cause of one of the most common cancers. Smoking causes over 70% of all lung cancers, and lung cancer is the third most common cancer in the UK.

But when it comes to other environmental factors, my aim is to work towards risk management, rather than complete risk avoidance. That means trying to be reasonably aware of risk factors, without taking it to the extreme in a way that might have a detrimental effect on your mental health, and it means weighing up the risks and benefits of activities, to reduce your risk where appropriate for you personally.

For example, sun exposure is a risk factor for skin cancer, and some forms of skin cancer are very metastatic and can be quite deadly, so reducing sun exposure is a reasonable risk management approach. But being outdoors has a lot of health benefits, and sun exposure is the best vitamin D source. So how do we balance the risk/benefits? We know sun beds are particularly high risk, so for me they are not an option. We also know that experiencing sunburn is higher risk – so we can take sunburn prevention steps, like wearing high factor SPF, and avoiding sun exposure during the sunniest parts of sunny days.

Ultimately, for people to take a risk management approach, they need to be reasonably well informed on what the risks are and how serious those risks are, and that is where governmental guidance can come into play.

There are lots of different types of guidance that look at lots of different areas but in the past weeks we’ve seen changes in the US’s Dietary Guidelines which were first introduced in 1980. These changes included some changes to dietary guidelines for alcohol consumption which were discussed by Dr. Mehmet Oz, the administrator of the Centers for Medicare & Medicaid Services in a news briefing. “In the best-case scenario,” he said, “I don’t think you should drink alcohol”.

The updated guidelines say that people should “Consume less alcohol for better overall health.” And that “People who should completely avoid alcohol include pregnant women, people who are recovering from alcohol use disorder or are unable to control the amount they drink, and people taking medications or with medical conditions that can interact with alcohol.”

This sounds quite good and balanced: reduce your alcohol intake, and in the best-case scenario don’t drink alcohol at all. This is advice I would give, and it is the advice of the WHO, who say there is no safe level of alcohol consumption.

We know that alcohol consumption increases the risk of certain cancers, and we know that it can lead to or contribute other health problems. When we’re discussing potential health benefits of consuming certain alcoholic beverages like red wine, the studies are often not about the alcohol, but about other ingredients in those drinks; they involve an ingredient that is not unique to alcoholic beverages; and they’re not actually measuring the intake of alcoholic drinks, but the specific ingredient in different forms in the lab. Resveratrol is the canonical example – any positive health benefits it might have are not limited to consuming it in red wine, and the quantities of red wine you’d need to consume to experience any resveratrol effects would mean that any positive would be vastly outweighed by the negatives of the increased alcohol consumption.

So, while I enjoy alcohol, and I am happy on a personal level to consume alcohol at a low-to-moderate level, I also know that I am increasing my risk of health problems, including cancer. And while I try to bring balance by maintaining a broadly healthy diet and incorporating other health promoting things like exercise, I know that the healthiest option would be to remove alcohol from my diet entirely. But autonomy is about making personal choices, and I get to choose which risks I take – as long as I am accurately aware of the consequences.

Assessing the consequences

Awareness of the consequences can be challenging, because research is not always clear cut, and the ways we talk about risk can be influenced by all sorts of factors. In the same moment that the US Dietary Guidelines were updated, media coverage also included headlines like “Alcohol causes cancer, and less than 1 drink can increase your risk − a cancer biologist explains how” from The Conversation, “Even one drink a day raises mouth cancer risk by 50%, study warns” from The Independent and “Just one alcoholic drink a day spikes mouth cancer risk by 50 per cent, concerning new research reveals” from The Daily Mail.

The Daily Mail explained

Drinking even a small amount of alcohol can increase your chances of developing mouth cancer by 50 per cent, according to a new study.

The research, published in BMJ Global Health, found that having just 9g of alcohol a day—which is just slightly over a standard alcohol unit—can make the likelihood of being diagnosed with the potentially fatal disease soar.

According to the Mouth Cancer Foundation, 10,825 people in the UK were diagnosed with the disease last year, and it was responsible for 3,637 deaths, more than cervical and testicular cancer combined.

So far, so scary. However, crucially, we are conflating cancers here. The study itself was looking at buccal mucosa cancer: cancer of the insides of the cheeks or lips, which makes up around 10% of mouth cancer cases. So, that immediately cuts those 10,825 people per year in the UK down to roughly 1,083.

This study is genuinely a really important piece of work, because the work was conducted in India, which is one of the areas where mouth cancer is particularly prevalent – though that is thought to be related not just to alcohol consumption, but to the high use of chewing tobacco in this region. Guidance in the UK already points to smoking, chewing tobacco and alcohol intake as risk factors for mouth cancer, and this research showed new evidence that combining chewing tobacco with alcohol intake compounds the risk, with 62% of the cases in the study attributed to this combination.

This is especially important research because we know mouth cancers are increasing, and we’re seeing an increase in the use of things like snus, the oral tobacco pouches which are held under the lip, tongue, or in the cheek. Yet the media focused on the alcohol factors from the study, omitting the contributing role of tobacco entirely from their headlines. We don’t even know if these data can even be extrapolated from India to the UK or other areas, since there are a whole range of other cultural factors which might influence this finding.

For example – the authors restricted the analysis to men, because pretty much 0% of women reported any alcohol intake. This is a suspiciously low level of alcohol consumption, which might be explained by the fact that the study is based on self-reported data, which means it has a level of unreliability. It seems unlikely that among the Indian women surveyed, none of them consumed alcohol; it seems more likely that they failed to accurately report what alcohol they consumed, because of cultural expectations and stigmas.

Scaremongering articles are never the way to highlight this sort of research, and while a 50% increase in risk of buccal mucosa cancer with 9g daily alcohol consumption per day is a significant finding, we should also be asking what a 50% increase actually means in terms of numbers. Unfortunately, I couldn’t find any data to tell me the specific prevalence of this type of mouth cancer in the UK, but bear in mind-that a scary-sounding increase of 50% might mean raising your risk from two in a million to three in a million. The absolute figures matter, if we’re going to accurately assess what risks we are comfortable taking.

Ultimately, we do know that alcohol consumption increases the risk of seven types of cancer: mouth, upper throat, larynx, oesophagus, breast, liver and bowel. This is because alcohol can both damage cells and prevent repair to damaged cells. Which is why those new US Dietary Guidelines are particularly strange. According to The New York Times, the previous set of US Dietary Guidelines which were issued in 2020 explicitly stated that even moderate drinking may increase the risk of cancer and some forms of cardiovascular disease as well as the overall risk of dying. This has been removed from the current guidance. Since the guidelines were first introduced in 1980, they have included specific guidance on the amount of alcohol that constitutes a reasonable limit with a suggestion to limit to one or two standard alcoholic drinks per day. Or more specifically no more than one alcoholic drink per day for women and no more than two alcoholic drink per day for men. This guidance has also been removed from the new guidelines.

And if we look at those guidelines again, we can see where this might be an issue, because the guidelines now say: “Consume less alcohol for better overall health”. But what does ‘less’ mean? For some it might mean cutting from eight drinks per day down to seven – a decrease, sure, but one that’s not really going to reduce your health risks in a meaningful way.

You may be tempted to think this is fine, because everyone already knows that alcohol consumption is risky. However, a study from the MD Anderson Cancer Center in Texas published late last year found that 53% of Americans don’t know that alcohol consumption increases your risk of cancer. Some − around 1% − even believe that drinking alcohol reduces your risk of cancer − presumably with a tip of the hat to those red wine drinking resveratrol rats. So removing these comments from the guidelines has potentially significant implications.

But what of Dr Oz? At least he told you that you should drink no alcohol at all, right? Well, yes, he did say that… but he also said that alcohol also provides “an excuse to bond and socialize, and there’s probably nothing healthier than having a good time with friends in a safe way.” And that in certain regions in Greece, Italy and Japan, where people live longer, they drink “very judiciously and usually in a celebratory fashion”.

So, do we think people take away from that, that alcohol has health implications? Or do we think that people will assume the social benefits of alcohol outweigh the risks? After all, he told us that “in the best-case scenario” we shouldn’t drink alcohol, and looking around the world, do we feel we are in the best-case scenario?

I’m going to leave the last word on this to the chief executive of the Alcohol Policy Alliance, one Mike Marshall (not to be confused with the editor of The Skeptic), who explained that as far as his group was concerned, omitting any mention the link with cancer is “a win for Big Alcohol”.

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