[Kirby64]

McDougall promotes a vegan fad diet. Not sure why I would trust his literature when there's plenty of contrary scientific evidence today. Also, it's been 16 years since that article was written. Scientific consensus has advanced considerably.

Just because humans survive on very little protein doesn't mean there are not negative implications, notably on muscle mass and development.

[0daystock]

Fad diet? Until recent history, and coincidentally before the prevalence of vast diet-related disease, most of the world lived on a mostly vegan diet. You are welcome to cite some of this advanced scientific evidence refuting McDougall or suggesting protein deficiency is a concern anywhere in the Western world.

[Kirby64]

McDougall's diet promotes low dietary cholesterol. Scientific evidence supports dietary cholesterol has no link to blood serum cholesterol. One easy example of promotion of non-evidence-based dietary restrictions. Also, extremely low fat recommendations, far below scientific concern levels. What's left is carbs and fiber for satiety, which is going to be extremely difficult to adhere to.

McDougall has also promoted his diet for treating diabetes, cancer, and other non-diet-related ailments.

Yes, I think it's fair to call it a fad diet. Nothing specifically wrong with reasonable vegan diets, but his seems full of specious claims.