Darn that diet, anyway.

Eating wisely may not be as easy as it sounds. Scientists report that some seemingly healthful foods, such as broiled chicken and baked fish, expose the diner to high concentrations of compounds that may damage the cardiovascular system--for example, by binding to blood vessel walls and making them less elastic. People with diabetes who have higher-than-normal concentrations of advanced glycation end products, or AGEs, in their blood are more likely to develop kidney and cardiovascular problems than are those with low concentrations, notes Jill P. Crandall of Mount Sinai School of Medicine in New York.

AGEs result from a complex reaction of sugars and proteins, and scientists have measured the amounts that are produced as a person digests food. AGEs are also abundant in some cooked food before it is digested, say the researchers. The team set out to see what effects diets containing foods high in AGEs might have on 11 people with diabetes.

Two weeks on a high-AGE diet increased the volunteers' average blood concentration of AGEs by 40 percent. In that time, concentrations of the AGE-linked cholesterol and the inflammatory compound tumor necrosis factor alpha (TNF-alpha) also rose significantly, notes Crandall. However, two weeks on a low-AGE diet that, for example, substituted poached chicken for broiled had the opposite effect. The diet lowered blood concentrations of AGE, AGE-linked cholesterol, and TNF-alpha.

Other researchers from Mount Sinai and the German Diabetes Research Institute in Dusseldorf have shown in laboratory tests that food-derived AGEs made blood clot more easily than normal. Such ready blood clotting can trigger strokes and heart attacks.

"You could be eating what you think is a healthy diet, but it could be bad for your diabetes," Crandall says.

--D.C.