Plant based experts
The doctors, researchers and teachers behind the plant based movement: who they are, what they are known for, and what they say, topic by topic, with links to where they said it.
متخصصان
Medical doctors (MD)
Caldwell Esselstyn MD. Surgeon and researcher at the Cleveland Clinic, author of Prevent and Reverse Heart Disease. John McDougall MD. Physician and founder of the McDougall Program. Dean Ornish MD. Physician, founder of the Preventive Medicine Research Institute and clinical professor of medicine at UCSF. Neal Barnard MD. Physician, founder and president of the Physicians Committee for Responsible Medicine (PCRM). Walter Willett MD, DrPH. Professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health. Michael Greger MD. Physician, founder of NutritionFacts.org. David Jenkins MD, PhD, DSc. Professor of nutritional sciences and medicine at the University of Toronto. Denis Burkitt MD, FRS. Irish surgeon and researcher. Walter Kempner MD. Physician at Duke University who created the Rice Diet. Hana Kahleova MD, PhD. Director of clinical research at the Physicians Committee for Responsible Medicine. Peter Rogers MD. Physician and YouTube educator.
Scientists (PhD)
T. Colin Campbell PhD. Professor emeritus of nutritional biochemistry at Cornell University, co-author of The China Study. Valter Longo PhD. Professor of gerontology at the University of Southern California, director of the USC Longevity Institute. Christopher Gardner PhD. Professor of medicine at Stanford University, director of nutrition studies at the Stanford Prevention Research Center. Doug Lisle PhD (clinical psychologist). Clinical psychologist, director of research at TrueNorth Health Center.
Dietitians
Other experts, not medical doctors
Nathan Pritikin Engineer and inventor. Inventor who created the Pritikin Program. Rip Esselstyn Former firefighter and triathlete. Founder of PLANTSTRONG, author of The Engine 2 Diet. Alan Goldhamer DC (chiropractor). Founder of TrueNorth Health Center, co-author of The Pleasure Trap. Jeff Nelson Publisher and media producer. Founder of VegSource.com. Chef AJ Chef and TV host. Host of Healthy Living with Chef AJ, creator of the Ultimate Weight Loss program.
What they say, topic by topic
- Vitamin B12 Vitamin B12 on a plant based diet: what McDougall, Esselstyn, Campbell, Barnard and other doctors say, where they agree and differ, with sources.
- Vitamin D Vitamin D on a plant based diet: what McDougall, Esselstyn, Barnard, Goldhamer and other doctors say about sun, pills and testing, with sources.
- Omega-3 fats Omega-3 on a plant based diet: what McDougall, Esselstyn, Barnard, Rogers and other doctors say about flax, fish oil and DHA, with sources.
- Oil Oil on a plant based diet: what Esselstyn, McDougall, Barnard, Willett and other doctors say about olive oil and no oil, where they agree and differ.
- Protein Protein on a plant based diet: what McDougall, Esselstyn, Campbell, Barnard and other doctors say, where they agree and differ, with sources.
- Calcium, dairy and bones Calcium, dairy and bone health: what McDougall, Esselstyn, Campbell, Barnard and other doctors say about milk, greens and osteoporosis, with sources.
- Iodine Iodine on a plant based diet: what McDougall, Barnard, Goldhamer and Rogers say about seaweed, iodized salt and pills, with sources.
- Calorie density Calorie density on a plant based diet: what McDougall, Barnard, Novick, Goldhamer and other doctors say, where they agree and differ, with sources.
- Nuts, seeds and avocado Nuts, seeds and avocado on a plant based diet: what Esselstyn, McDougall, Campbell, Barnard and other doctors say, where they differ, with sources.
- Soy Soy on a plant based diet: what McDougall, Campbell, Barnard and Rogers say about tofu, hormones and cancer, where they agree and differ, with sources.
- Salt Salt on a plant based diet: what McDougall, Goldhamer, Barnard, Novick and other doctors say, where they agree and differ, with sources.
- Sugar Sugar on a plant based diet: what McDougall, Esselstyn, Barnard, Goldhamer and other doctors say about added sugar, honey and fruit, with sources.
- Starches Starches on a plant based diet: what McDougall, Esselstyn, Barnard, Novick and other doctors say about potatoes, rice, grains and beans, with sources.
- Fasting Fasting on a plant based diet: what McDougall, Barnard, Goldhamer, Kahleova and other doctors say about water fasts and eating windows, with sources.
- Supplements Supplements on a plant based diet: what McDougall, Esselstyn, Campbell, Ornish and other doctors say about multivitamins and pills, with sources.
- Iron Iron on a plant based diet: what McDougall, Campbell, Barnard and Rogers say about anemia, iron overload, pills and absorption, with sources.
- Fish and eggs Fish and eggs on a plant based diet: what McDougall, Esselstyn, Barnard, Ornish and other doctors say, where they agree and differ, with sources.
- Fiber Fiber on a plant based diet: what Burkitt, McDougall, Barnard, Ornish and other doctors say, where they agree and differ, with sources.
- Fruit Fruit on a plant based diet: what McDougall, Esselstyn, Barnard, Goldhamer and other doctors say about how much, juice and sugar, with sources.
- Vegetables and greens Vegetables and leafy greens on a plant based diet: what McDougall, Esselstyn, Barnard, Goldhamer and other doctors say, where they agree and differ.
- Beans and lentils Beans and lentils on a plant based diet: what McDougall, Esselstyn, Barnard, Goldhamer and other doctors say on amounts, gas and cans, with sources.
- Whole grains, bread and flour Whole grains, bread and flour on a plant based diet: what McDougall, Esselstyn, Barnard and Novick say about flour, white rice and gluten, with sources.
- Potatoes Potatoes and sweet potatoes on a plant based diet: what McDougall, Esselstyn, Barnard and Novick say, where they agree and differ, with sources.
- Meat Meat and processed meat on a plant based diet: what McDougall, Esselstyn, Campbell, Barnard and others say, where they agree and differ, with sources.
- Low-fat eating How low in fat should a plant based diet be? McDougall, Esselstyn, Ornish and Campbell on 10% fat, where Willett differs, with sources.
- Saturated fat Saturated fat on a plant based diet: what Esselstyn, McDougall, Barnard, Willett and other doctors say about animal foods, coconut and heart risk.
- Cholesterol Cholesterol on a plant based diet: what McDougall, Esselstyn, Barnard, Ornish and other doctors say about targets, LDL, HDL and food, with sources.
- Carbohydrates and low-carb diets Carbs, keto and low-carb diets: what McDougall, Campbell, Barnard, Ornish and other doctors say, where they agree and differ, with sources.
- Gluten and wheat Gluten on a plant based diet: what McDougall, Campbell, Barnard and Goldhamer say about wheat, celiac disease and sensitivity, with sources.
- Coffee, tea and caffeine Coffee, tea and caffeine on a plant based diet: what McDougall, Esselstyn, Barnard, Goldhamer and other doctors say, with sources.
- Alcohol Alcohol on a plant based diet: what McDougall, Campbell, Barnard, Goldhamer and other doctors say about wine and beer, where they agree and differ.
- Chocolate Chocolate and cocoa on a plant based diet: what McDougall, Esselstyn, Ornish, Goldhamer and other doctors say, where they agree and differ, with sources.
- Juicing and smoothies Juicing and smoothies on a plant based diet: what McDougall, Esselstyn, Barnard, Goldhamer and other doctors say, where they agree and differ.
- Organic food and pesticides Organic food on a plant based diet: what McDougall, Campbell, Barnard and Goldhamer say about pesticides, cost and labels, with sources.
- Mediterranean diet The Mediterranean diet beside a plant based diet: what McDougall, Esselstyn, Barnard, Novick and other doctors say on olive oil and PREDIMED, with sources.
- Weight loss Weight loss on a plant based diet: what McDougall, Esselstyn, Barnard, Ornish and other doctors say and found in their studies, with sources.
- Cravings and food addiction Food addiction and cravings: what McDougall, Barnard, Goldhamer, Lisle and other doctors say, where they agree and differ, with sources.
- Exercise Exercise on a plant based diet: what McDougall, Esselstyn, Barnard, Ornish and other doctors say, where they agree and differ, with sources.
- Heart disease Heart disease and a plant based diet: what Esselstyn, Ornish, McDougall, Barnard and other doctors say and found in their studies, with sources.
- High blood pressure High blood pressure on a plant based diet: what McDougall, Esselstyn, Barnard, Ornish and other doctors say and what their studies found, with sources.
- Diabetes Diabetes on a plant based diet: what McDougall, Barnard, Ornish, Kahleova and other doctors say and found in their studies, with sources.
- Cancer Cancer and a plant based diet: what McDougall, Campbell, Ornish, Barnard and other doctors say and what their studies found, with sources.
- Dementia and the brain Dementia and Alzheimer's on a plant based diet: what McDougall, Esselstyn, Barnard and Ornish say and found in their studies, with sources.
- Longevity and aging Longevity and aging on a plant based diet: what McDougall, Esselstyn, Ornish, Goldhamer and other doctors say and found, with sources.
More topics are on the way: fruit, starches, protein, meal timing, sugar, salt and exercise.
How we write these pages
A position is credited to a person only from their own byline, newsletter or voice on video. Organization websites are labelled as such, because several contradict their founders. Where we found no clear statement, we say so instead of guessing.
Each topic compares everyone against one plain statement and marks who agrees, partly agrees or disagrees, with the strength of the evidence behind their advice.
This guide summarizes what each person has said in public; it does not recommend any diet. Every position links to its source, to the exact second for videos. Sources checked 2026-10-10.