The supplement companies would be pretty happy. I can imagine that health would decline, even as waist lines got smaller. Cholesterol is a much needed building block for many important bodily functions including in the brain and nervous system. Vit. D would be even harder to get and the problems vit. D deficiency causes would increase even faster than it is now. The open land for cattle then have to become farms for vegetables and grains - most likely conventionally grown - causing just as much if not more pollution from the fertilizers and chemicals needed to grow so many more crops.
Humans evolved to be omnivores and our bodies do better if we balance our diet, not eliminate an entire type of macro-nutrient.
we would all tend to live longer as PROVEN by scientific studies. there would be more food to go around, as people could eat the volumes of grain now fed to cattle. the environment would improve.
this said, i am not a vegetarian currently (have been) as my husband doesn't consider it dinner without meat. we don't eat red meat regularly, however, as it raises heart attack, colon cancer, and pancreatic cancer risks.
The French are pretty healthy they include animal protein in their regular diet. People have been trying to find out why they don't have as many heart problems. Perhaps it's their joy of life which includes a joy of eating good food. Joy is healthy.
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