"But fructose is is the core of many fruits which are considered as healthy."
No, the core of many fruits considered healthy is FIBER(mainly cellulose) . We do not metabolize fiber but fiber has three important effects on us:
1) It is "in between" the sugar, lowering the effective concentration of sugar on blood. When you drink sodas all the sugar goes to the blood in a very short amount of time, this creates emergency responses on the blood control systems:
Biological control systems are very similar to PID controllers(we copied them from nature), with things like overshooting happening.
No, the core of many fruits considered healthy is FIBER(mainly cellulose) . We do not metabolize fiber but fiber has three important effects on us:
1) It is "in between" the sugar, lowering the effective concentration of sugar on blood. When you drink sodas all the sugar goes to the blood in a very short amount of time, this creates emergency responses on the blood control systems:
Biological control systems are very similar to PID controllers(we copied them from nature), with things like overshooting happening.
http://en.wikipedia.org/wiki/Overshoot_%28signal%29
This is the reason a lot of tennis players eat bananas now in between the game.
2) Fiber creates an environment to bacteria on our intestines to live. This bacteria flora helps us a lot in a lot of ways.
3)Fiber makes easier to transport waste as it hydrates.
This of course is an oversimplification, but you get the idea.