Fructose and HFCS: Once again the "skeptics"* are wrong.

[GaYellowDawg]

69. Wrong on almost all counts.

First, fructose has not "long been known to be toxic." Fructose is actually present in most fruits. Like anything else, excessive fructose intake has consequences. In smaller amounts, it generally is split into two 3-carbon chemicals by the liver that can either help replenish glycogen or build triglycerides. In larger amounts, after glycogen is replenished, the excess will mainly be converted to triglycerides, which are the body's method of fat storage. It's no surprise, then, that excessive amounts of HFCS can readily cause obesity, but fructose is not toxic.

Second, many sugars - and many carbohydrates - don't have fructose as a subunit. Table sugar (sucrose) does. Maltose does not. Lactose does not. Starch does not. Soluble fiber does not.

Common granulated sugar is half fructose. It's a disaccharide, meaning that each sucrose molecule is made up of one glucose and one fructose. So you got that one right.

HCFS is a little worse than sucrose, but not for the reason you described. HFCS contains glucose and fructose separately, not combined into a disaccharide. Therefore, in HFCS, no fructose "is broken away from the sucrose molecule." The only difference in processing is that sucrose requires an additional step which involves splitting it into glucose and fructose by using the enzyme sucrase. However, the metabolic cost for that is negligible. The reason why HCFS is worse is because its fructose content is 5% higher than sucrose. Therefore, someone who consumes a lot of sweet stuff will tend to gain adipose tissue slightly faster. Of course, this effect becomes more pronounced as someone consumes more HFCS.