Humankind has probably been eating some minor amount of fruit and nuts seasonally, supplementing game meat and fish, throughout most part of our ancestry, that is a couple of millions of years, probably. It is highly unlikely that such food would suddenly turn out to be generally harmful. That cannot be said about some more recent plant derived food produce consumed in unprecedently large quantities - most notably the grains.
Ancient Egyptian mummies have been found riddled with "modern" degenerative diseases, including heart disease, rheumatoid arthritis, diabets and other. From eating fish and meat? I don't think so! The grains are the most likely culprit!
Mass consumption of grains (and starchy vegetables!) has only been possible since the advent of modern style agriculture, settled communities using fire and cooking, that is around 7500BC in the Middle East and somewhat later elsewhere.
DMW mentioned the plants' anti-oxidant.
I think that is a very complex subject. If you read the refs I posted in the other thread, they may indicate that consumption of plants is a double-edged sword. It adds antioxidants and vitamins but it also accelerates DNA damage.
On the positive side:
- yes it is better to eat plants than nothing, if nothing else is available. Regardless of what has been said a death by starvation is worse than eating some dodgy wild fruit or vegetables, for a short while, until a next successful hunt or fish catch.
- yes, plants do contain soma anti-oxidant and vitamins, but also ...
on the negative side:
- those same plants may contains some phytotoxins and large amount of compounds (notably fructose) that generate troublesome metabolic byproducts using up those anti-oxidants and vitamins (i.e. carbs metabolism requires vitamin C) and tying up a large portion of body's immune system for cleanup.
- most plants' macronutrients are not very compatible with human digestion and requirements. Most commonly available plants are very high (too high) in carbohydrates. Those that are not high in carbs are often (with some rare exceptions) high in the type of fats (polynsaturated) that are not as well tolerated as animal fats, in large meal staple quantities. Those plants that are not very high in carbs and fats, are high in a kind of proteins (aminoacids) that are also not well matched to human requirements.
Heretic
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