Regardless of the biochemical pathways, Fructose is found in plants, as with many other compounds found in nature, we are "designed" to process it...
The end of those reactions produce molecules critical to our function. Like cholesterol, cholesterol is fantastic, without it, well, say good by to bi-lipid membranes for starters...
The issue here is dosage- stop stuffing your gob with anything that resembles an edible and most of the "modern problems" will clear up.
You need to learn something about a condition called “reactive hypoglycemia.” People develop it for a variety of reasons, but commercial use of HFCS combined with the SAD (high-fructose corn syrup/Standard American Diet) have greatly increased the incidence in the population. Hunger, however induced or enhanced, is a powerful thing; people have been known to eat their children with hunger as the strong driving force. People will benefit by studying human nutrition as well as history.