... on a side note, I once shared an apartment for 1 year with a buddhist monk who put me on his raw food diet, I never felt so alive in my life! My whole body felt like it was singing. But it's really a difficult diet without someone to manage it, and we were also living in the Lower East Side of Manhattan, ground zero for the raw food diet movement.
What tends to happen with raw/vegan diets is that the person feels great in the beginning because they cut out a lot of junk/processed food, but after a period (which can be months to years), problems related to micronutrient deficiencies usually appear. I have been researching nutrition & health for many years and looked into the raw/vegan long-term effects, and what tends to happen is that after the initial "high", eventually they realize they feel better on a diet that includes animal foods. Of course, this is not highly publicized because the vegan community looks down on and ostracizes the ex-vegans that have the courage to admit they feel better when they start eating animal foods again.
Also, more recently a lot of people are healing from all kinds of chronic diseases (especially autoimmune) with a carnivore diet -- eating nothing but beef and water in the most strict version. The hypothesis is that some people are more sensitive to plants' defensive toxins (which most plants contain, to defend from predators), so avoiding plant foods helps them heal (meat contains no such toxins since animals' defense is running away/fighting). Cooking deactivates some of these toxins, so for people who are sensitive to them, raw plant foods have the worst effect. More on plant toxins and their potential negative effect on our health
here if anyone is curious.
If we look at human evolutionary biology, it's very clear that we need animal foods to thrive. Humans evolved the big brain we have in part because of animal foods, and also cooking, which allowed our body to use less energy for digestion and more for brain development. So, a raw vegan diet sounds great in theory (especially when compared to the Standard American Diet/SAD) but is actually quite far from the human species' natural diet.
Just as an example,
this paper by a nutritionist argues that plant-based diets "risk worsening brain health nutrient deficiency", such as choline deficiency (choline is essential for brain health, and even more so for pregnant women, and animal foods, especially eggs and liver, are the richest sources of choline).
The book "Catching Fire: How Cooking Made Us Human", by Harvard primatologist Richard Wrangham, is great on this topic.
Summary: "Humans (species in the genus
Homo) are the only animals that cook their food, and Wrangham argues
Homo erectus emerged about two million years ago as a result of this unique trait. Cooking had profound evolutionary effect because it increased food efficiency, which allowed human ancestors to spend less time foraging, chewing, and digesting.
H. erectus developed a smaller, more efficient digestive tract, which freed up energy to enable larger brain growth. Wrangham also argues that cooking and control of fire generally affected species development by providing warmth and helping to fend off predators, which helped human ancestors adapt to a ground-based lifestyle. Wrangham points out that humans are highly evolved for eating cooked food and cannot maintain reproductive fitness with raw food." (PS From this perspective, Buddhist monks of course aren't worried about reproductive fitness
)
You can do ok on a vegan diet *if* you really track your micronutrients and plan your foods very carefully, but it will never be as health promoting as a diet that includes (minimally processed) meat/fish/eggs/other nutritious animal foods (and ideally also liver or other organs). Also in the case of women, it can be really easy to get iron deficiency anemia on a vegan diet. Iron deficiency is a huge public health problem in third world countries (especially in women and children), where people tend to eat mostly plant-based diets (since meat is expensive). Studies have shown that when they add meat to these children's diet, their physical and mental development greatly improves. Of course, this is not talked about in the "meat is bad" circles.
PS I have a Master's in Nutritional Epidemiology from the Harvard School of Public Health, which is strongly in the "meat is bad" camp, and I have been a member of several carnivore diet groups for a year now, and been learning a lot about the benefits they are seeing -- so I have seen both sides of the meat debate in detail
