Wishes for a perfect world

I got another wish:

A good understanding of what is and isn't beneficial regarding human nutrition.

My guess is we'll find there are types of digestive systems, if by that we include the effects of various proteins, fats, carbs, vitamins, amino acids and even contaminants on different people. That is, a high-fat diet may be inimical or beneficial for some people, but harmful for others.

Consider this analogy: is a high-history brain "diet" good or bad? Well, it would depend on the individual involved, wouldn't it? Some knowledge of history is good for everyone, just as everyone needs some amount of fats, say. But intensive study of it wouldn't be as beneficial for an accountant with little interest in it than for a novelist with a keen interest and a desire to write period pieces.

Already we know of conditions that are affected by diet. Some, like diabetes, are indeed diseases (ie malfunctions of the body's systems). The human body uses glucose and other sugars as energy. On the other hand, is celiac disease really a disease? Or lactose intolerance?

Pure speculation, of course.

High fats and oils in an Eskimo diet doesn't seem to bother them but when they start eating sugar, their teeth rot and they become diabetic.

Westerners would eat a high meat diet didn't seem to bother them too much but people often died fairly young anyway.

French women who come to the USA but maintain a French lifestyle rarely put on weight.

Viking restaurants seem to have healthy customers as to places where they serve Medieval Food (I don't mean American food with Medieval trappings for entertainment value) I mean authentic Medieval dishes served in bread bowls.

Quote: Fleastiff

Westerners would eat a high meat diet didn't seem to bother them too much but people often died fairly young anyway.

The highest cause of death until the 20th
century, in adults, was infectious disease.
People didn't live long enough to die
from what we do now. Sugar is a newcomer
to Eur, it's only been available for a few
hundred years. People fared better without
it. Cane sugar, that is. The used honey
sparingly before that.