(Ivanhoe Newswire) -- A drug used to treat gout seems to protect against blood pressure increase in men on a high-fructose diet, according to new research.

"This is the first evidence of a role of fructose in raising blood pressure and a role for lowering uric acid to protect against that blood pressure increase in people," Richard Johnson, M.D., co-author of the study and professor and head of the division of Renal Diseases and Hypertension at the University of Colorado–Denver medical campus was quoted as saying.

In the study, excessive fructose consumption seemed to increase new onset of metabolic syndrome, associated with cardiovascular disease and type 2 diabetes. The gout drug seemed to halt it — most likely by lowering uric acid, which affects blood pressure.

Fructose is the only common sugar known to increase uric acid levels. One of several dietary sugars, fructose makes up about half of all the sugar molecules in table sugar and in high-fructose corn syrup, a sweetener often used in packaged products because it is relatively cheap and has a long shelf life. Glucose makes up the other half.

Patients with high blood pressure, diabetes and kidney disease often have high uric acid levels and gout. But all the ways in which those conditions might contribute to the development or worsening of the others isn't completely understood, Johnson said.

Johnson and co-author Santos Perez-Pozo, M.D., a nephrologist at Mateo Orfila Hospital in Minorca, Spain who led the study, evaluated 74 men, average age 51, who consumed a diet that included 200 grams of fructose per day in addition to their regular diet. This amount is much higher than the estimated U.S. daily intake of 50 to 70 grams of fructose consumed by most U.S. adults. Half the men were randomly assigned to get the gout drug allopurinol and the other half acted as controls.

After only two weeks on the diet, the high-fructose plus placebo group experienced significant average blood pressure increases of about 6 millimeters of mercury in systolic blood pressure and about a 3 mm rise in diastolic blood pressure.

In contrast, men on the high-fructose diet plus allopurinol had significantly lower uric acid levels and virtually no increase in systolic blood pressure. The blood pressure levels of most of the men returned to normal within two months of the study's conclusion when the participants returned to their normal dietary intake, Johnson said.
The study also found changes in the incidence of metabolic syndrome, defined as having three or more of these five risk factors:
• Increased waist circumference;
• High triglyceride levels;
• Low levels of high-density lipoprotein (HDL);
• High blood pressure;
• High fasting blood sugar.
After just two weeks, the incidence of metabolic syndrome more than doubled in the men who consumed a heavy fructose diet and took the placebo pill.

Among men consuming fructose plus allopurinol, virtually no change in the rate of metabolic syndrome occurred — perhaps because the gout drug prevented the blood pressure rise associated with increased fructose consumption.