The consumption of soft drinks appeared to influence hyperuricemia, a strong risk factor for gout, while eating purine-rich vegetables and certain dairy products showed no such association in recent study results.
In a population-based, case-control study conducted from 1999 to 2006, researchers in Scotland investigated plasma urate concentrations in 2,037 healthy people (mean age, 62 years; 44% women) to determine associations with sugar-sweetened beverages (SSB), purine-rich vegetables, dairy products and related nutrients. Using a quantitative food frequency questionnaire (FFQ), dietary data were collected. FFQ and composition of foods information was used to calculate nutrient intake, and urate concentration was measured in plasma.
The mean urate concentration was 283.79 mmol/dL (women: 260.06 mmol/dL; men: 302.28 mmol/dL). With cut-off values of greater than 415 mmol/dL for men and greater than 340 mmol/dL for women, researchers classified 11.3% of women and 5.2% of men as hyperuricemic.
Using multivariate regression analysis, researchers found:
- A significant association between SSB and plasma urate (P=.008). For participants who were drinking two or more SSB servings daily compared with those who did not drink any, SSB was 13.7 mmol/dL (P=.06).
- No association between consuming purine-rich vegetables and urate (P=.38). The mean number of daily servings of purine-rich vegetables was 1.9 tablespoons.
- An inverse association between skim milk (P=.02) and low-calorie yogurt (P=.04) with urate concentrations. Mean daily consumption of dairy products was 335 g.
- No statistically significant association between dietary fructose and plasma urate (P=.66). Free fructose intake was 24.7 g daily and total fructose intake was 55.9 g.
“The lack of significant association between purine-rich vegetable intake and plasma urate challenges the appropriateness of recommendations to restrict purine-rich vegetables in hyperuricemic individuals and gout patients,” the researchers said. “The abundant evidence supporting the inverse association between urate concentration and dairy consumption should be reflected in dietary guidelines aiming to lower plasma urate.
“Further studies are necessary to establish which nutrients and food products causally affect plasma urate.”
Disclosure: Researcher Dr. Felix Agakov is employed by Pharmatics Limited.