Monkeys banned from eating bananas at Devon zoo
Zookeepers say the stereotypical food actually makes monkeys more aggressive, rots their teeth and can lead to diabetes
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Zookeepers said the fruit grown and exported for human consumption have far higher levels of sugar than the ones monkeys would eat in the wild – to the point that it’s bad for their teeth and can lead to diabetes.
https://www.independent.co.uk/news/uk/home-news/monkeys-bann...
Maybe due to selection of larger, sweeter fruit, yes. But processed food contains various sugar variants, including fructose (think "high fructose corn syrup") so fruit isn't the only (not even the main) source of fructose for many.
This is a little mixing of apples and oranges but the high fructose we tend to eat are much higher than primates that eat fruit.
And "high fructose corn syrup" is ... almost pure fructose. Which the human liver can only process a limited amount per day.
Anecdote: a young guy in Freiburg (Germany) got Covid recently and as a result lost his sense of taste afterwards. Now he isn't interested in fast food any more as everything tasty "bland" and can "easily" eat vegetables which he disliked before, even broccoli or Brussels sprouts. Which made him loose more than 50 pounds. Don't get this wrong, it's not an incentive to get Covid, but an example of the effects of abstaining from fast food and soft drinks.
[1] https://en.wikipedia.org/wiki/High-fructose_corn_syrup#Compo...
Meanwhile humans can eat concentrated fruits. Imagine picking and eating 100 grapes, vs eating a handful of raisins.
Whole fruit contains vitamins, minerals, fiber, and significant amounts of water. Whole fruit contains intact plant cell walls. It's very important to eat intact plant cell walls, but that's difficult to determine from studies of isolated nutrients. Because of the bulkiness caused by water and fiber in whole fruit, it's difficult to eat large amounts. For example, it takes about four oranges to make a glass of orange juice. Most people would not eat four oranges, but most people could easily drink 1 or more glasses of juice.
The wild fruit eaten by primates has less sugar and more fiber compared to fruit cultivated by humans. Human cultivated foods, including plants and livestock, are much richer compared to wild plants and animals, having more fat, sugar, starch, and calories in general, than what could evolve in the absence of pest control.
Humans have evolved quite differently than other primates. We have a rare ability to digest large amounts of starch, a capability shared almost exclusively with rats and pigs. It's difficult to compare our diets.
Primates consume significant amounts of foliage (leaves and such). You probably should too, green leaves are very excellent for your health.