It is worth bearing in mind that a lot of things we consider to be food really does not want to be food. Grains want to be carried away by the wind to plant themselves somewhere else. Their ancestors invariably had toxins in them to dissuade any creatures (including us) from eating them.
Not one single animal, insect or fish has evolved specifically to be eaten. Hence the wide range of defensive measures most animals/insects/fish have to make sure that does not happen too often. Again, toxins come into play. As you move up the food chain so you get an accumulation of those toxins, hence we tend not to eat apex predators.
Compare and contrast with fruit. Fruit has evolved specifically to be eaten, particularly by primates. The idea being that we eat some fruit, wander off to somewhere new, have a dump, eject some seeds from the fruit complete with a handy amount of manure and water. Yep, those pesky plants tricked us into doing all of their work for them! They even managed to get us to cover up our leavings, thereby planting their seeds properly.
Our vision system co-evolved with fruit, we (as in primates) see in colour not because god wanted us to live in some world of puppies and rainbows but so we could eat fruit that is ripe and ready to eat. The plants, knowing that we were evolving colour vision, kindly evolved through some process of natural selection to produce fruit that kick in to 'eat me' colours when they are nice 'n' ripe.
With this colour coded system it is possible for plants to avoid waste. We (as in primates) only pick the ripe fruit, the stuff that is still green is identifiably no good to us so we leave it until it magically changes colour.
Obviously there came a time when grasslands took over and we had to leave the trees, learn to stand up and walk on two feet (so we could see over the grass) and find new meals to try. At this stage the cult of eating dead animals was borne, we adapted, but not that much, our intestines are still a million miles longer than that of a dog, we still have hands for nabbling fruit rather than vicious claws to rip apart stray wildebeest and we can still chew, as you need to do for fruit, in a way dogs don't do.
Much like how multi-vitamins are of dubious benefit to you, so it is with fructose. Sugars in fruit are fine, nobody has died of diabetes due to eating too many apples. The 'fibre' is an important part of it, you need 'fibre' if you are to consume sucrose.
The problem with diet in America is corn. There is nothing edible about corn grown in America today unless it has been processed by an industrial process or another animal first. All of those corn-stuffed animals Americans eat get killed before the corn kills them. If Americans are not careful they will be remembered as 'the corn people' like some of those American Indian tribes that tried and failed to build corn-based civilisations in pre-Columbian times.