Abstract
High intakes of dietary fructose comprise a significant component of sugar-sweetened beverages (SSBs) and have been associated with increased serum uric acid concentrations and the metabolic syndrome. To date few studies have investigated the effects of reducing fructose concentrations on serum uric acid, the metabolic syndrome and its components. Therefore we conducted an eight week randomised, controlled trial recruiting relatively insulin resistant adults who had high habitual intakes of SSBs (> 500ml/d). Each participant was instructed to replace his or her habitual SSB intake for sugar-sweetened soft drink (control), artificially sweetened soft drink, 100% pure orange juice, or low-fat, flavoured milk. Metabolic and anthropometric data were collected at weeks 0, 4 and 8. Dietary data and urine samples were collected at weeks 0 and 8. Substantial decreases in uric acid were observed in all groups compared with the sugary-sweetened soft drink group (-34, -38, -43µmol/L respectively; p < 0.015). No statistically significant changes in metabolic syndrome components were observed. However the study was powered to detect changes in uric acid so it is not possible to draw definitive conclusions regarding effects on body weight, waist circumference, body fat percentage, systolic and diastolic blood pressure, and both total and HDL cholesterol.
Our trial shows replacing SSBs with other beverages significantly decreases levels of serum uric acid. If uric acid is a pivotal component of the constellation of risk markers associated with insulin resistance a reduced intake of SSBs may be an important feature in the management of the metabolic syndrome.