Is Dr. Harriet Hall’s Review of “What The Health” Legit?

Dr. Harriet is a popular science and skeptic blogger who says that several people asked her to review the documentary “What the Health”. She watched it and took notes. I also read her “review” and took notes. Let me share mine with you. Quoted parts are her own statements. (Note: I made a YouTube video (of the same name) and this is only a transcript. I can’t be assed to add all the pictures and format this whole thing from my OneNote since this won’t be read by anyone anyway.)

It starts off pretty badly.

It starts with Hippocrates’ aphorism “Let food be your medicine and medicine your food.” Hippocrates died in 370 B.C., before there was much in the way of effective medicine and before science had learned much about food (like the existence of vitamins). So Hippocrates is hardly a credible authority; and even if he were, the appeal to authority is a logical fallacy.

“Hippocrates existed a long time ago, therefore what he has to say can’t possibly be relevant to us.” Also, quoting him is a logical fallacy! Let’s see.

“My SkepDoc’s Rule: before you accept a claim, try to find out who disagrees with it and why.” <— this is me quoting a seemingly wise piece of advice. From whom? Well from Harriet Hall! Of course, she is a  Doctor, and a Skeptic. So, Did I just commit an appeal to authority? No Harriet, an appeal to authority takes the form of first establishing that someone is an authority, and secondly, that whatever they say on the topic that they’re an authority on, is probably true, as in, you’re encouraging others not to examine the claim for themselves.

1.Harriet Hall didn’t like What The Health and says it’s vegan propaganda.
2. Harriet is a Doctor and Skeptic. She runs a well-known blog which is not funded by industry.
3. Therefore, you can trust that What The Health is vegan propaganda (without looking into it yourself).

This is an appeal to authority. And this is, funnily enough, what this article serves to accomplish for many people. Most people who will link this article on Reddit, Facebook or elsewhere do so only after they’ve read the conclusion, which appears at the very top, and claims that this is vegan propaganda. Why do they do this? Well of course, because they have their own confirmation bias to protect.

He cites a summary of epidemiologic studies showing that eating a single serving of processed meat a day increases colon cancer risk by 18%. In the first place, epidemiologic studies can only show correlation, not causation.

Yes, Harriet, you’re right. To hell with all observational data. We, the real scientists and skeptics, only want double blind, randomised, placebo-controlled, crossover trials to establish cause and effect. Anything else is just shoddy science!

What Harriet is saying here is that, we have no evidence that parachute use prevents death and trauma related to jumping off of planes. That’s right — where is the evidence that parachutes help prevent death? Where are the trials? Well then, we have no reason to recommend people use parachutes before jumping off planes. Ah, the wisdom of skeptics. (

The film tries to convince viewers that food is medicine, and indeed is all the medicine we need to prevent and cure obesity, diabetes, heart disease, cancer, and a host of other chronic diseases. It failed to convince me.

Did someone say, appeal to personal incredulity? Wait, isn’t Doc Harriet aware that this is a logical fallacy?


He proceeded to interview doctors and others who subscribed to that belief, and to find supporting information on Google. Confirmation bias worked well, as it always does.

This is true. What Harriet fails to mention is that no one escapes confirmation bias. And she has a pretty clear anti-vegan bias to defend herself.

Processed meat

Harriet claims that the documentary is alarmist, and that the risks associated with disease from eating processed meats “in moderation” are in fact very low and pretty much trivial:

 By one estimate, your risk of developing colon cancer by age 65 is 2.9% if you eat no processed meat, and 3.4% if you eat one serving a day. So out of 100 people who avoid processed meat, 2.9 will develop colon cancer, and out of 100 people who eat one serving a day, 3.4 will develop colon cancer: the difference in absolute risk is one more case of cancer out of every 200 people, which sounds much less alarming than the 18% figure.

First, Harriet mentions “one serving” but fails to mention what that serving is, and how people typically eat. The serving mentioned is a serving of 50g. Everyone that I know who buys and enjoys processed meat, even when they think they are doing so in moderation, eat more than 50g of it per day, and usually per serving. These high fat, high salt foods–usually also containing some sugar– are addictive in nature. A couple slices of bacon are unlikely to “hit the spot”. But this is downplayed here.

 And there could be many confounding factors that would influence a person’s actual risk like genetics, salt consumption (processed meats like bacon have a high salt content), smoking, other lifestyle factors that might happen to be more common in people who eat a lot of processed meats, etc.

This is a very misleading paragraph and just shows more of Harriet’s bias influencing her judgment. Confound factors are by definition outside factors. Saying that it may be the high salt content of processed meat that is responsible (whether in part or entirely) for the increase in cancer risk is like saying that arsenic in cigarettes is a confounding factor when you smoke. The meat becomes processed meat because it’s been cured–i.e. Salted. It’s intrinsic to the product if it’s termed processed meat and not a confounding factor.

Harriet’s deceptive suspicion of salt being a major culprit here is likely to make one who trusts her judgment & simply look for low sodium meat products instead. What she ommitted to say is that the WHO answered this question:

In short, she is once again selling her audience short.

Secondly, the study in question established cause and effect. They found mechanistic data to support the link between processed meat and cancer, which is why it is in the Class 1 category. It’s the most robust form of evidence we have, which means that confounding factors were removed as best as they can ever be removed. Why is she mentioning them?

Lastly, go look at the UICC’s website which she gets her information from.

There are sponsored by so many organizations who actually benefit from people being sick. Of course they will be fine downplaying this. The American Cancer Society is there as one of their “Patrons programme”, sponsored by the meat industry of course. I lost count at how many pharmaceutical industries are partnered with them. Oh wait, am I being paranoid? A tinfoil hat wearing conspiracy theorist? No, it’s there for everyone to see.

Harriet then claims that the documentary says that eating processed meat is just as bad as smoking cigarettes. No, they simply said it was put in the same category. People can interpret that differently, sure. Harriet suggests that the documentary deliberately makes it vague for them to do so. But you can be sure that most reasonable people will know that if it was just as dangerous as tobacco smoking, they wouldn’t be first hearing it from this documentary.

But they did NOT recommend people stop eating meat. They explain, “Eating meat has known health benefits. Many national health recommendations advise people to limit intake of processed meat and red meat, which are linked to increased risks of death from heart disease, diabetes, and other illnesses.”

We all know that national health recommendations are imperfect and industry influence plays a big part in those recommendations. The WHO must still support them, but that doesn’t mean we have to blindly accept this. Who is the skeptic here again?

How much meat in one’s diet has “known health benefits”? There are no sources to those claims. We have no reason to believe that the exclusion of meat from one’s diet will make one’s health likely to be worse than with the inclusion of some meat. And it seems wholly arbitrary. Where is the “tolerably daily intake” data?

Oh wait, they actually answered this right underneath where Harriet cherry-picked:

  1. How much meat is it safe to eat?

The risk increases with the amount of meat consumed, but the data available for evaluation did not permit a conclusion about whether a safe level exists.

Gee, couldn’t we just say that it’s reasonable to better be safe than sorry, then?

Red Meat

Reality check: the movie presents an alarmist version of information that has been widely accepted for decades and is incorporated into nutritional guidelines. The consensus is that processed meats should be limited; but the data on unprocessed red meat is unclear. Only vegans recommend total elimination of meat.

This is patently false. It’s amazing how easily people accept the sugar industry’s manipulation of data due to how much money & power they have, but aren’t willing to do so with Big Meat, Dairy and Egg. It has taken an enormous amount of effort by groups like PCRM to get the nutritional guidelines to change towards a more favorable one, based on science, notably with MyPlate. Nutritional guidelines have always been a compromise between what’s good for the industries and what’s good for the consumer. Here in Canada we have only just started discussing the new suggestions that plant sources of protein should be favored. It hasn’t even made it to the official guidelines yet.

We know how confusing the guidelines have been and how the big lobbysts create this fog around nutrition: “Reduce saturated fat and replace with unsaturated fat” which basically means reduce high fat dairy and meat and consume more plant fats. The average person does not get that message and does not benefit from reading this and that is why the guidelines were made to be vague and confusing.

A recent study looked at the association between dietary factors and mortality from cardiovascular disease and diabetes. As a whole, ten dietary factors accounted for 45.4% of deaths. Only 0.4% of these deaths were associated with a high intake of unprocessed red meats, and 8.2% with a high intake of processed meats.

But wait, I thought epidemiological studies could only ever prove correlation and not causation. What about all the confounding factors she referred to earlier? Why does this paper, which has only been cited once, interests Harriet Hall so much? I don’t know. Why did she not review the paper with the 70% figure from the documentary instead? It comes straight from the CDC which she quotes right after this. I couldn’t access this paper because it’s behind a paywall so I can’t comment on it. One thing I will say is that, once again she appears to be downplaying the significance of adopting a plant-based diet which abandons red meat and processed meats. She gives us these figures separately as if eating didn’t involve an opportunity cost. You’re not only cutting out red meat and processed meats by doing so, you’re necessarily increasing your intake of other foods, most likely fruits, vegetables, legumes whole grains, nuts and seeds, (in the context of plant-based eating). All of which are inversely associated with death and disability. That’s a huge deal. The study concludes that “Dietary factors were estimated to be associated with a substantial proportion of deaths from heart disease, stroke, and type 2 diabetes.” which backs up this very point. So, now we’re left arguing just how substantial that portion is.

 According to the CDC, somewhere between 20% and 40% of the top five causes of death could be prevented by lifestyle changes, but not just dietary changes. Tobacco is the leading preventable cause of death, not improper diet; other important lifestyle factors are alcohol use, lack of exercise, sun exposure, and failure to use seatbelts and motorcycle helmets. The 70% estimate is an exaggeration; the true proportion of lifestyle-preventable deaths is probably less than 50%. And diet has a relatively small impact when compared to other lifestyle factors. The movie tells us dietary factors trump smoking, but that is demonstrably not true. It tells us plant-based diets will stop and reverse heart disease, and breast cancer can be prevented by diet; I wish!
Digging into this, I found that there seems to have been contradictory figures given out by the CDC. I tried finding the 70% figure on their website but couldn’t find it. But it wasn’t made out of thin air by the documentary makers: I found a paper which quotes the  CDC saying that, “Chronic diseases—such as heart disease, cancer, and diabetes—are the leading causes of death and disability in the United States. Chronic diseases account for 70% of all deaths in the U.S., which is 1.7 million each year (85). These diseases also cause major limitations in daily living for almost 1 out of 10 Americans or about 25 million people (85), The CDC further wrote, “Chronic diseases – such as heart disease, stroke, cancer, diabetes, and arthritis – are among the most common, costly, and preventable of all health problems in the U.S.”

It appears the CDC changed this information but I couldn’t verify it with the Wayback machine (archive of snapshots of web pages at different times).

Either way, we have to go with what they’re currently saying. Or do we? The Global Burden of Disease study, a more recent study and the largest, most rigorous analysis of risk factors ever published, funded by the Bill and Melinda Gates foundation, found that dietary risks trump tobacco smoke for death and disability in the US.



And here’s the GBD study graph for the year 2010. That 70% figure doesn’t seem too far off now, does it?

Diet has a relatively small impact when compared to other lifestyle factors, says Mrs. Hall. Really?

We are in the midst of a (type II/adult-onset) diabetes epidemic. The movie tells us diabetes is not caused by sugar: meat and fat cause diabetes. It says carbs can’t make you fat; only fat can. It says the body can’t turn carbs into fat (yes, it can!). They cite a Harvard study showing that one serving of processed meats a day raises the risk of diabetes by 51%, but this 2017 systematic review says it raises the risk by 19%. And remember, this is relative risk, not absolute risk.

The study is in fact from 2010 but shows up as 2017 for some reason. Now, this is pretty nit-picky again from Harriet, downplaying the effects of a food we know causes disease. “Remember it’s only relative risk, which as we have established earlier, means almost nothing!”

She presents this systematic review as if it was necessarily better than the Harvard study, but she doesn’t explain her rationale. Meta-analyses are not necessarily more reliable. For instance, as Dr. Dean Ornish says,

“The fact that not all studies have shown this risk does not mean that it is not true. In doing large-scale studies in which people complete dietary surveys, there is often so much noise—especially in combining data in meta-analyses—that a type 2 error often occurs (that is, the noise obscures the ability to detect statistically significant differences).”

In the next few paragraphs, Mrs. Hall does more of the same. She finds studies that haven’t found an association or ones that conclude the opposite from the ones mentioned in the documentary. She never goes into detail about the merits and shortcomings of each individual studies though. Yawn. She thinks it’s enough to say that there is contradicting data out there to discredit the studies mentioned in the documentary. It’s not. It just goes to show how confusing the nutritional sciences are.

Harriet claims that “Fruits and vegetables contain carcinogens too!” She says that because the documentary film doesn’t mention them, but mention the carcinogens in animal foods, they create a double standard. This is absurd. And for some reason, she doesn’t provide any source for her statement. Which fruits and vegetables contain naturally occurring carcinogens? Is she (mistakenly) confusing nitrates and nitrites? Is she referring to the pesticides? And most importantly, just how carcinogenic are they, and do they have other active compounds in the food that are anticarcinogens? What is the overall effect of the food? For instance, we know that if half of the US population were to increase their consumption of organically grown fruits and vegetables, an estimated 20,000 cancer cases might be avoided each other. But when it’s conventionally grown, we might only prevent 19,990 cases of cancer a year instead. That still warrants an increase in fruit and vegetable consumption by a long shot, despite the carcinogens in the conventionally grown fruits and vegetables.  (
But we have no data to suggest that an increase in meat, dairy or egg consumption could actually do something like this, do we?

But again, Harriet has her own agenda: it appears that she is not particularly interested in lifestyle medicine. She wants you to throw your hands in the air and just go, “Well, whatever, everything causes cancer. Might as well just eat everything in moderation, it doesn’t worth it to carefully weigh the pros and cons so you can minimize risk as much as possible.” And that’s fine. No one says you have to care. But don’t turn your own apathy into advice.

Harriet’s following 5 paragraphs are just descriptive statements of what is said in the documentary. There is no critique. There is one more appeal to personal incredulity fallacy, but not much else. I don’t know what to make of this. She wasn’t kidding when she said she took notes. These are literally just notes on what is being presented; not criticisms.

Eventually, she does offer a few exclamation points and a question mark when she’s describing Dr. Michael Greger’s take on endotoxins in meat causing inflammation. Apparently, Impaired Flow-Mediated Dilation and postprandial inflammation caused by endotoxins is really wild, unbelievable stuff. We have to take it on faith that it is, because she doesn’t review the literature that he refers to.

Harriet then complains that the documentary is anti-conventional medicine. She claims conventional medicine owns prevention. This isn’t really the case. The doctors featured in this documentary all were conventionally trained. They acknowledge that if you are dealing with an acute condition, conventional medicine is the way to go. They make a point to say that chronic illnesses are largely preventable and conventional doctors are not trained to help you prevent it or reverse it. Harriet thinks that because doctors have cured things like smallpox, they “own” preventative medicine. The thing is, smallpox being a virus, it wasn’t caused by lifestyle factors. Preventative medicine, as it currently exists, seeks to educate people on risk factors they actually have control over, so this is a red herring.

Harriet then claims that Doctors are trained in nutrition and “understand the principles but leave individual diet advice to the dieticians”.

Harriet proceeds to talk about Kip Andersen’s phone calls to various organizations and how they (seemingly) have no interest in talking about preventing or reversing illness. She immediately assumes that they are one-hundred percent committed to prevention and cure and the reason they don’t want to argue is because “the evidence isn’t there”. You mean, the evidence of all the populations that live on plant-based diets and who avoid the diseases of affluence we get in the West? That’s not missing.

She follows up with a false analogy relating autism and vaccines and diabetes reversal and lifestyle modification. As if there was the same amount of (lacking) evidence for both of these. This is pretty astounding ignorance on her part.

Many of the arguments for veganism are not health-related but moral. Animals suffer from being confined, conditions are unsanitary, they produce greenhouse gases and are bad for the environment.

Yes, veganism has benefits beyond one’s personal health. That’s a cold hard fact. But instead of seeing this as a fact, Harriet (and other veganism detractors) will claim that vegans are often motivated by these other agendas, in spite of whatever health problems veganism might come with. This is simply untrue. Vegans want veganism to be sustainable long-term and they would not benefit from deceiving people for altruistic reasons. It would only be a matter of time before they revert back to omnivory if it wasn’t a healthy enough way to live.

Harriet’s just about to conclude her piece and mentions how all of these testimonials are unbelievable (literally so). This is where I have to sympathize with her. She clearly has no one in her environment who has made the switch and who improved their health or reversed a chronic condition, and she hasn’t done it herself. It stands to reason that you should be skeptical of any testimonial from people you don’t know and can’t verify the validity of their stories. She mentions being skeptical of athletes who say their recovery time has improved dramatically. I also think there is some wishful thinking when it comes to veganism and athleticism and I haven’t been able to find the data to support some of those claims. I also haven’t experienced it.

She ends up taking literally what seems like an obvious metaphor by the filmmaker and decries his rejection of the age-old tripe that is “everything in moderation”. Her argument is that “the evidence doesn’t show that everything in moderation is unhealthy!”. Actually, just like the “do parachutes prevent death? lack of evidence”, we don’t really need it; common sense suffices here. One of the first things you learn when you take a nutrition course is that we live in an obesogenic environment. In other words, the environment is full of traps; and unless you are informed and have sufficient willpower, you will be in harm’s way. But willpower is understood to be a limited resource, and life can throw a curveball at you at any time which weakens your internal resources. Everyone has heard this saying and probably believed it at one point in their life, yet we are in the middle of the biggest chronic disease epidemic in human history. As Beth Skwarecki says, “When your favorite diet advice is the same as junk food peddlers’ favorite diet advice, maybe you should reconsider.” She wrote a great article on this topic and I will be linking it below.

Harriet’s conclusion: Spectacle, not science!

The movie cherry-picks (but she doesn’t), it’s alarmist, and it will probably harm you if you follow its recommendations (that’s implied)! If you were worried that you might have to rethink your diet, worry no more, renown skeptic Harriet Hall has come to the rescue to tell you that you might want to eat a teenie bit more plant foods, but you don’t have to worry one bit “until there is more evidence”. Yeah, you shouldn’t have worried about tobacco smoking in the 50s either because most doctors smoked!  What was the American Medical Association’s rallying cry back then? “Extensive scientific studies have proved that smoking in moderation by those for whom tobacco is not specifically contraindicated does not appreciably shorten life”  Sound familiar?

many of us would rather accept a small hypothetical risk than give up the foods we love

And that’s the whole point: if you want to take the risk, you should be able to, but in order to do that you have to be made aware of that risk first. Health care professionals who patronizingly don’t even bring up lifestyle modification because they think people are unlikely to change aren’t doing that. As an authority figure, you should be nudging people into making better decisions, not telling them to make the most comfortable one. It’s a comforting illusion to say, “we just don’t know enough”.

In conclusion, let me say that I don’t believe the movie was without flaws. It’s clear to me that they took some liberties to make the movie more engaging. I also found some pretty dubious pictures or “memes” being shared on their Facebook page too. And if I was to judge Kip Andersen superficially from a quick visit on his Facebook, the New Age vibe he gives off doesn’t really inspire confidence.

But the film he made is still vastly superior to the others I have seen, which typically use sugar as a scapegoat for the obesity epidemic and the associated increase in metabolic syndrome occurrence. All of these documentaries are one-sided too, but they don’t have the excuse of having a good reason for it to be. They’ll blame industry influence when it suits them and ignore the influence of Big Meat, Egg and Dairy.

There are a great many reasons to adopt a vegan diet. Even if it turns out that some of the science they referred to in this doc is iffy, what’s the worst that will happen as a consequence? Will you be harmed because you’ve started eating more whole plant foods after seeing it? Probably not.

Can you get over the fact that they focused on something that has never been focused on in a documentary before? They had limited resources to make this documentary. The reason they didn’t bother with sugar is not because they think sugar consumption is perfectly fine, but because it is already at the forefront of people consciousness. Everyone and their mother knows that refined/added sugar is bad for you now.

They also didn’t get into Paleo or so-called “ethical omnivory”, which Robb Wolf decried on his blog, because they have already went into the fact that it’s unsustainable in their previous film “Cowspiracy”. Why bother investigating it on the health level when only an elite few can ever partake in it?