On the other hand, a vegan diet based on whole foods, not processed like oils and flours, and avoiding too much omega-6 oil and sugar has an astonishing range of health benefits.
I'm surprised this site hasn't been posted / discussed on HN before:
Historically, we can trace our brain development alongside evidence of the use of fire. I would never use the raw-food diet because science tells me it's not adequate. Regardless, it may have health benefits.
Child mortality pulls down the average:
http://www.livescience.com/10569-human-lifespans-constant-2-...
While adult life expectancy has increased somewhat thanks to sanitation and antibiotics, there has never been a time when adult life expectancy was a mere 35 years.