In the 1970s, food manufacturers began using a man-made sweetener called high-fructose corn syrup (HFCS) as an inexpensive substitute for sugar. Diabetes in the U.S. has climbed considerably since then. Science has yet to prove these events are linked, but a recent study may have turned up a smoking gun.
Last summer Rutgers University researchers reported that HFCS-sweetened soft drinks contain astonishingly high levels of compounds called carbonyls, which happen to be elevated in diabetic patients and contribute to the grim complications of the disease. A single can of soda can contain more than five times the amount found in the blood of diabetics, says study coauthor Chi-Tang Ho, PhD, professor of food chemistry at Rutgers.
A reaction between unbound fructose and glucose molecules during the manufacturing of HFCS produces carbonyls, Ho says. They thrive in the acidic environment of soda. "We're concerned that frequent soda drinkers, particularly children, may suffer detrimental consequences," he says.
Ho explains that table sugar doesn't cause the same problem because its fructose is bound, though Peter Havel, PhD, a professor of nutrition at the University of California, Davis, points out that the heat of baking can free sugar's molecules. That's why he believes fructose in general plays a role in the increased diabetes trend. What's worse, Havel's research shows that fructose facilitates weight gain and drives up triglycerides—a type of blood fat that can harm arteries.
The next step is to see how many of the compounds are absorbed into the blood, says Ho. Of course, you don't have to wait for the results to know that reading labels to avoid added sugar is a wise idea, he says.