Forks Over Knives



Forks Over Knives is a 2011 American film that purports to show that "most, if not all, of the degenerative diseases that afflict us," such as cancer and heart disease, can be controlled or eliminated through a vegan diet. The movie is a presentation by documentarian Lee Fulkerson of the claims of Dr. T Colin Campbell (author of The China Study) and Dr. Caldwell Esselstyn.

Claims
The primary claim in Forks over Knives is that a diet including animal products not only leads to obesity and obesity-related conditions, but also to cancer.

On the subject of obesity, the documentary details the works of diet-based doctors, such as Dr. Esselstyn, who claim they can reverse obesity, type II diabetes, and heart disease by switching a patient to a 'whole-food, plant-based' diet. The documentary supports this claim with data from The China Study, a book published in 2005 by Dr. Campbell that examined population data in China to demonstrate a correlation between animal products consumed and "Western-type diseases" such as heart disease, diabetes, and other afflictions. There are supplemental studies, such as a 2009 study that indicated that rats that were fed the milk protein casein later displayed higher cancer rates. The film also bases its claims on the case histories of patients seen by Dr. Caldwell Esselstyn at the Cleveland Clinic.

The documentary dips into historical investigation, as in its discussion of Germany's WW2 occupation of Norway. During this period, the Nazis seized much of Norway's food assets, such as livestock, butter, and cheese. Dr. Esselstyn maintains that local incidence of heart disease dipped drastically, due to the removal of animal products from the Norwegian diet.

Criticisms
The statistical methods of The China Study have been challenged. In a blog article by writer Denise Minger. Rebuttals of her criticisms may be found by other authors, including T. Colin Campbell. The issue of dietary choice and health is controversial and complex, making a neutral presentation of this documentary film difficult.

Usage of the term "animal products."
Not all animal products are the same. It is sloppy to lump all animal products into one big category, encompassing the KFC "Double Down", salmon, plain egg whites, ostrich meat, sirloin steak, bacon, crabs, goat milk (and its delicious cheese), and spider morsels in one group. It would be similarly useless, for example, to claim that "plant products" are unhealthy for children because nightshade is poisonous. Yet people don't balk in general at the 'sloppiness' of a doctor's advice to eat more fruits and vegetables. Recommendations are often easier to follow by being pithy; a cold-turkey approach is sometimes best even if a little turkey won't kill you, and science, while dependent on details, often abstracts away details in order to focus on relevant generalities. In other words, there are broad differences between whole plant foods and unrefined animal foods -- for instance, all foods in one of these categories contain essentially zero dietary fiber -- and these may be relevant to nutrition. The crucial question is whether there are enough scientifically-grounded, directionally aligned differences between the nutritional features of the two groups to justify the advice.

Plant products are healthy, look at these beautiful happy endings where veganism saved the lives of these people!
What this documentary doesn't mention is that these people didn't go on just any plant-based diet. They went on very specific diets, ones that eliminated not only animal products but also all oils, including vegetable oils such as olive oil. Further, the restrictive nature of this diet eliminates all of the junk that they were eating before (though that's kind of the point -- it's the definition of junk food that is in question). It's hard to tell if weight loss, reduced diabetes and heart disease correlate with a plant-only diet - or with the simple elimination of junk food.

Animal-based diets are Western, and plant-based diets are Eastern.
This is a disguised appeal to ancient wisdom instead of common sense: using orientalism to imply that non-Western cultures are somehow inherently wiser, and thus more healthy than Western cultures, despite the unfortunate colonialist background of such thinking. Forks Over Knives pretty much tries to associate the racist concept of "wisdom of the Orient" with veganism, to imply that because many Asian people do not eat (or do not have access to) animal products, they are therefore healthier, wiser, and should be emulated. Without this overly-positive association of 'Eastern' ideas, the concept of plant-based diets occurring in Asian populations would be completely value-null and useless to this video attempting to convince watchers to stop eating animal products now.

Vegetarianism as a conscious lifestyle choice is relatively rare in China, for example. While there is a global distinction in eating habits, it is almost solely one rooted in disparate levels of wealth and industry; producing enough meat, at affordable prices, and making it available to the general population requires not only a relatively rich country, but one with a firmly established meat industry that is able to deliver the goods. In many meat-eating countries and regions, agriculture of animal products as well as plant products is subsidized to a degree. In areas that still rely on subsistence farming or have poor agriculture support systems, animals are very time, labor, and resource-intensive to care for and as a result diets contain more plants. And again using China as an example, arguing that the people whose diets are very low in meat are healthier than the average American is to be in complete denial of reality; beriberi (vitamin B1 deficiency) is still a major problem due to the difficulties of preserving rice, whereas in the West it is extremely rare and usually the result of chronic alcohol abuse.

Usage of the term "Western diet"
If this sounds exactly the same as the usage of "Western medicine" in alt-med discussions, that's because it is. This documentary, despite its support by actual doctors, is a promotion of a kind of alternative medicine: the idea that serious diseases not only spring from dietary regimes but can also be resolved by changing them. Most medical practice accepts diet as one factor among several others when it comes to heart disease and diabetes. Diets that are high in saturated fat and salt, for example, can help cause serious cardiovascular problems. However, Forks Over Knives goes a step further than medical science can credibly support, claiming that the promoted vegan diets can actually cure "Western-type diseases."

Poor anecdotal evidence.
A major claim in Forks Over Knives is that diet is the key factor in cancer, type-II diabetes, and heart disease cases. Yet the anecdotes provided as evidence for this claim are misleading. In several of these anecdotes, the individuals didn't simply change their diets: the patients in question changed their whole lifestyle.

It is not mysterious that a man who stopped eating junk food and began to exercise more would have more energy and lower his cholesterol. Nor is it unheard of that type-II diabetes, which can result from poor health habits, might improve with a significant change in lifestyle. But in Forks Over Knives, the shift away from animal products is claimed to be the decisive factor.

Lack of mention of portion sizes
One major contributor of obesity and related health problems the documentary fails to address is the increase in serving sizes. The diet shift the documentary urges obviously dodges distorted portion sizes restaurants serve. People did eat fast food back in 1970, didn't they? The problem today is they're unknowingly devouring more of the bad stuff from both fast food and sit-down restaurants. Sit-down restaurants fare even worse because they do not have the same negative aura fast foods have, so they have more room to go out of control with portion sizes.

The China study
Dr. Campbell's China study faces stern criticism for omitting key data and results for the sake of its conclusion. Correlation not being causation is a major issue with it; it ignores many other correlations discovered for the sake of the ones that display evidence for a meat-cancer link.

Norway in World War II
Although it is true that Norway's livestock was requisitioned in WWII, Forks over Knives leaves out the black market trade of such goods in a wartime country, as well as wholesale substitutions in the diet. For example, fish was much more widely consumed, to the point of fish roe being dried and ground up as a stretcher to add to rationed flour in bread, and people experimented with eating moss and seagull. Locally gathered gulls eggs have long been a part of the diet. Many households also started raising their own livestock. The removal of livestock does not instantly indicate a shift to a vegan diet. Nor should it, because correlation does not equal causation. It should also be pointed out that Norway, along with any other country occupied by Nazi Germany, was subjected to food rationing, which started out at 2000 calories per day per person, but quickly fell below 1500 calories after 1942 and below 1300 during and after the Winter of 1944, leading to a rise in deficiency-related diseases. It is not surprising that "mortality from circulatory diseases" would be falling in a population subjected to rationing, war, atrocities, and the Holocaust. In the UK, which had more gentle rationing similar to that in Norway early in the war, the restrictions were associated with improved public health not only by removing unhealthy products from the diets of many people, but also providing more nutrition for the very poor.

Casein and rats
Regardless of the findings, it is somewhat questionable that the effects of isolated casein ingested by rats might apply to the effects of hundreds of different animal proteins ingested by humans, especially when many of those proteins are accompanied by other substances found in animal products that may alter the effect on the body, such as whey which is usually found alongside casein in milk and has reported anti-cancer properties.

Presentation
This documentary is loaded with weasel words when it comes to veganism. Although they don't call it a vegan diet. Instead, they call it a "whole-food, plant-based diet." Presumably this is to avoid the loaded term of veganism, which invokes images of dirty hippies, PETA, and environmentalism issues to some. Just to be fair, however, french fries, soda, white bread, candy, pure sugar, and soft shell crab-flavored Pringles are all "plant-based" and vegan (if not colored or flavored with carmine or castoreum extract), so the addition of "whole-food" is most likely to invoke unrefined plant food.

In addition, it uses many heartstring-tugging anecdotes of how people went onto very strict vegan diets and ended up losing weight, solving their health problems, diabetes, heart disease, etc. Although the stories are valid, they are a very clear show of pathos. Even the most critical reviewer had to admit she liked the feel-good stories, even if they added nothing to the credibility of the claims.

And finally, this documentary plays upon a modern American fear of poor health and body angst to sell its ideas.

The possible aim
While the film repeatedly slams money-obsessed business practices and attempts to cast suspicion on the good will of conventional medicine, it is not a pure-intentioned messenger of wisdom, truth, and broccoli. While a few approved recipes appeared on their site, the exact details of the magic diet(s) are unknown... unless you buy some of the advertised books!

The "FoK Diet" page is helpful enough to prominently link to many of these titles, and even offers a convenient "book packaging" service to make it even easier to buy multiple books.

There's nothing wrong with pointing consumers to these books and commercial diet programs, of course. But this is a program that has been presented as an ostensible public service, because the public needs to change their diets. But the proposed alternate diet, so heavily emphasized in the film, seems to actually be several different diets. Some of these diets are not strictly vegan, and include items such as honey, and each is the brainchild of different doctors. And while they have some common traits, their most prominent aspect is that they all want your money.

The takeaway
While lowering your meat intake may have health benefits, going completely vegan may not have the dramatic effects Forks over Knives claims. In addition, the film attempts to support these conclusions through many fallacious arguments such as correlation equalling causation, anecdotal evidence and emotional appeal, among others. While the film does make a couple good points, one should keep these in mind and approach with caution.