Walter Bushell wrote:
Doug Freyburger wrote:

I have no wish to push anyone who is a vegetarian for religious, moral
or political reasons to stop. Some reasons are worth the slightly lower
health. And people who practice for those reasons tend to follow
traditional systems that are well designed so they don't have health
impacts. Rather like the few Inuits who still live the traditional
hunting lifestyle on the ice are very healthy even though they eat
nothing but (very broadly defined) meat for months on end.

But ah, vegans in England ran into problems with B12, because the
grains in England did not contain as many insects as in India. A
little human dung (or from other animals) in the vegetables also helps.

It's the "traditional systems are well designed" bit. Well evolved
actually. Modern people who suddenly decided to go vegan did not have
the benefit of centuries of tradition that give time for details to
evolve to make a diet healthy.