What Does Your Doctor Think of “What The Health”?

Tiffany Lester, MD
August 10, 2017

At Parsley Health , our doctors have been bombarded by questions about the recent documentary What the Health that premiered on Netflix in March 2017. The goal of the film is to get people to adopt a vegan diet. To do this, the filmmakers employ scare-tactics backed by medical professionals. If taken at face value, the claims made would almost certainly cause the average person question their diet.

On the one hand, we appreciate that the film brings to light the fact that organizations like The American Cancer Society and The American Heart Association, which many look to for dietary recommendations, are funded by meat and dairy companies and have close ties to the pharmaceutical industry. However, the abundance of misinformation in the film is staggering.

Several of the health claims in the film are grossly exaggerated or are based on limited data. In order to bolster its thesis that a vegan lifestyle is the healthiest way to prevent or reduce your risk for cancer, heart disease and diabetes, the movie misreports studies. In truth, no diet is a cure-all. At Parsley Health, we create personalized diets for each member based on their digestive health, food intolerances, autoimmune conditions and ethical preferences. At the end of the day, eating a diet that is plant-based, low in sugar and alcohol, and free from processed foods will lead to a healthier mind and body.

One of our core tenets is to be “a better doctor.” We define this as a doctor who knows how to access and objectively interpret the best available data in the context of individual patients and their unique and personal values and goals.

This is what each of our physicians has to say about What The Health:

Robin Berzin, MD, Founder/CEO Parsley Health

“The film focuses on animal products, yet sugar can be just as dangerous. Sugar causes inflammation in a number of ways. First sugar causes oxidative stress in the body, damaging DNA and shortening telomeres , leading to faster aging. Additionally, sugar causes insulin spikes which signal your cells to move sugar from the bloodstream into your adipocytes (fat cells), which then grow and multiply. These cells then produce chemical messengers called cytokines which activate the immune system on a chronic basis – this chronic activation is known as inflammation. The science of sugar is well documented and not to be underestimated.”

Lilli Link, MD, Parsley Health New York

“As a long-time follower of a vegan diet, I would love to give What The Health two thumbs up; sadly, I cannot. To the film’s credit, it does cite some very interesting studies that show the benefits of a vegan diet. However, what it neglects to discuss is that the level of scientific evidence in favor of a vegan diet is still weak. For example, the movie discusses a study done by Dr. Dean Ornish which examined the effects of a vegan diet on prostate cancer. What you aren’t told is that this was a pilot study with only 93 men, it included other lifestyle changes like exercise and stress management, and has yet to be replicated. While I agree with some of the film’s premises, specifically that a vegan diet can be incredibly healthy if done correctly and that most animals that are raised for consumption are treated inhumanely, we simply don’t have the evidence to support the claim that a vegan diet is the healthiest diet. Hopefully one day research will provide a clearer answer.”

Jeffrey Egler, MD, Medical Director, Parsley Health Los Angeles

“I found the film compelling but, as all documentaries are, somewhat biased. Much of the information is valid and reasonable and, quite frankly, I’m glad it concerns people. They should be concerned. Simply put, processed food is not healthy. It’s designed to produce mass quantities of subsistence for large populations of consumers, generating substantial profit margins in the process. The problem is that the film only looks at the issue in black and white (industrial farming/meat/dairy industry vs. a whole, plant-based diet), without considering the gray area. There is a large and expanding movement of organic, whole, humanely-treated, natural food products, including both meat and diary, that are free-range and grass-fed. These are undoubtedly much healthier than the highly processed meat and dairy products which the documentary presents as the only meat and dairy options available to consumers.”

Soyona Rafatjah, MD, Parsley Health New York

“The claim that drinking milk causes cancer is most certainly an overstatement. While I do believe that milk can increase digestive discomfort, mucus production, and inflammation in many people, making a broad statement that milk directly causes cancer is false. To scientifically prove that A (milk) causes B (cancer), you have to create an isolated environment wherein A (milk) can be tested and its effects on the production of B (cancer) can be observed over time. No such study has been done. Some researchers have looked at populations that consume more milk and noted the general association between these groups and incidence of cancer, however, there is a plethora of other factors that could be contributing to this increased risk for cancer.

Tiffany Lester, MD, Medical Director, Parsley Health San Francisco

“The film makes sensationalized and misleading statements; for example, saying that the effects of eating 1 egg a day is equivalent to smoking 5 cigarettes per day, in terms of life expectancy. Eggs have gotten an undeserved reputation as one of the leading causes of high cholesterol. The suggestion that the higher saturated fat content in eggs accelerates altherosclerosis (hardening of the arteries) as much as smoking does is false. New research from both the Harvard School of Public Health and the National Institute of Health have debunked this concept. Eggs are a cornerstone of a healthy diet and contain vital nutrients like choline, selenium, and Vitamin B12.”

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  1. https://www.ncbi.nlm.nih.gov/pubmed/23676423

  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2386667/#!po=14.4231

  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2676999/

  1. http://amp.timeinc.net/time/84514/nearly-half-of-us-deaths-can-be-prevented-with-lifestyle-changes/?source=dam

Tiffany Lester, MD

Dr. Tiffany Lester is a board-certified Integrative Medicine Physician who has practiced a holistic approach to health for over a decade. She is a graduate of the University of Cincinnati College of Medicine, where she completed her training in internal medicine. She also graduated from the Integrative Medicine Fellowship at the University of Arizona with Dr. Andrew Weil, and has extensive training in functional medicine through the Institute of Functional Medicine. Dr. Lester is also featured as a teacher for the Institute of Integrative Nutrition and regularly contributes to national wellness publications.

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