Sweetened soft drinks contain large amounts of fructose, a sugar derived from fruit, which increase levels of uric acid.

However, no studies have investigated the link between these beverages and the risk of gout, Dr. Hyon K. Choi told Reuters Health.

These findings provide the first evidence that fructose and fructose-rich foods are important risk factors for gout.

Choi, from the University of British Columbia in Vancouver, and Dr. Gary Curhan, from Harvard Medical School in Boston, used food questionnaires to assess consumption levels of soft drinks and fructose in 46,393 men enrolled in the Health Professionals Follow-up Study who were gout-free at study entry and were followed for 12 years.

During that period, 755 men developed gout, and the risk was related directly to levels of sugar-sweetened soft drink consumption.

Compared with soft drink levels of less than 1 serving per month, consumption of 5 to 6 servings per week, 1 serving per day, and 2 or more servings per day, increased the risk of gout by 29 percent, 45 percent, and 85 percent, respectively.

A similar trend was noted with fructose consumption. Compared with subjects who consumed the lowest fructose levels, those who consumed the highest had an increased gout risk of 102 percent.

Consumption of high-fructose fruits, such as apples and oranges, was also associated with an increased risk of gout.

Alcohol is a "well-established, strong risk factor for gout," Choi noted.

However, the strong increase in gout risk associated with sweetened soft drinks and fructose was "rather surprising," especially because current dietary recommendations for gout focus on the restriction of alcohol and the amino acid purine, but have no restrictions on sugar-sweetened soft drinks or fructose.

In light of these findings, Choi advises doctors to steer their gout patients and patients with high uric acid levels away from sugary soft drinks.

As for recommending reductions in high-sugar fruits, he said the risks versus the benefits need to be considered on a patient-by-patient basis.

Further research is needed to see if these findings also apply to women, Choi added, and to determine if fructose is associated with cardiovascular disease and other major disorders related to high uric acid levels.

(Agencies via China Daily February 9, 2008)