Segway listed as #1 on list of 50 worst inventions.

[Tristan Lall]

Originally Posted by artdutra04

Eliminate high-fructose corn syrup from your diet. It's not natural, and the enzymes in your stomach can't break it down easily. Thus, your body doesn't accurately know when it's full, and you'll tend to eat more food than you need.

While overall message in your post is reasonable, the quoted point is pretty much entirely wrong.

1. "Natural" means nothing in this context. The product is chemically simple enough that it wouldn't matter if it was derived from plants or petroleum (through some creative organic chemistry). You're just getting glucose and fructose. (Glucose and fructose are the same sugars that combine to form common sucrose, and, along with water, are the principal chemical constituents of high-fructose corn syrup.) The implication that natural things are generally better for people is a dangerous falsehood.
2. Stomach enzymes don't break down glucose and fructose. (You might be thinking of amylase, which makes simple sugars from starches. Glucose and fructose are already simple sugars, and don't need to be broken down in the mouth or stomach.)
3. The satiation reflex is complicated and it's not correct to summarize it in terms of false premises. Bulk of food, appetites for specific chemicals (e.g. sodium) and other factors act more quickly and directly than the response to oxidative metabolism. (Digestion takes hours.)

There's a grain of truth to the idea that high-fructose corn syrup has some impact on health. Fructose is one step further along the glycolysis process than glucose is. And because the step that converts glucose to fructose consumes adenosine triphosphate (ATP, the chemical that your body uses as a unit of energy for immediate use), you use slightly more energy metabolizing glucose than fructose, when using the glycolysis metabolic pathway. However, most fructose doesn't get used in glycolysis (via phosphorylation), and instead is undergoes another metabolic process, fructolysis, in the liver. That means that the (slightly) increased concentration of fructose in high-fructose corn syrup will cause a relative increase in fructolysis and a decrease in glycolysis.

There's no scientific consensus on the health consequences. Both glycolysis and fructolysis are normal processes in healthy animals, and it's unclear whether more of one and less of the other poses a risk to human health. Studies are underway to determine if there are measurable problems with metabolizing proportionally more sugar in the liver (glycolysis takes place everywhere; fructolysis is localized in the liver).

Many of the myths surrounding corn syrup are the product of people who don't understand to any extent whatsoever the biological processes at work, and are drawing conclusions based on this lack of understanding. The only thing they get out of it is the dubious proposition that "HFCS makes you fat". This is why high school biology is useful, even to non-biologists.