Sugary High Hurts Your Heart

Sept. 24, 2009— -- A diet high in fructose can increase uric acid levels, but the drug allopurinol may help lower the resulting high blood pressure, researchers say.

Men who took the drug to mitigate the effects of a high-fructose diet did not experience the increase in blood pressure observed among men on the same diet who did not take the drug, Dr. Richard Johnson, of the University of Colorado said at the American Heart Association's High Blood Pressure Research Conference in Chicago.

"These results support the idea that fructose, such as present in table sugar and high-fructose corn syrup, could have a role in the epidemic of obesity and metabolic syndrome," Johnson said. "Further, they suggest that [the two sweeteners] could have a role in high blood pressure, and that this might be mediated by uric acid."

Eating a lot of fructose -- typically from sugary drinks sweetened with high-fructose corn syrup -- has previously been associated with increased levels of uric acid.

"It has been known for a long time that fructose can raise uric acid levels, and in the last few years epidemiological studies have also confirmed that those with the highest fructose intake have higher uric acid levels," Johnson said.

Johnson added "reducing sugar intake was an old treatment for gout as well, and was even espoused by Sir William Osler." Osler was a renowned physician widely credited with advancing modern medicine.

Dr. Robert Lustig, of the University of California San Francisco, was a co-author on a paper in the Journal of Pediatrics published last summer that found evidence of this link in adolescents. The more sugary beverages the teens consumed, the greater their serum uric acid levels and, hence, their systolic blood pressure.

"The fact that this paper addresses this mechanism in humans rather than just rats is extremely important," Lustig said.

But he cautioned that uric acid is likely not the only cause of the metabolic syndrome.

"I absolutely think that uric acid is the main driver of hypertension" with regard to fructose consumption, Lustig said. But he added uric acid may not be the driver of body fat and high cholesterol that are other components of the metabolic syndrome.