Purine-rich foods, dairy and protein intake, and the risk of gout in men

BACKGROUND: Various purine-rich foods and high protein intake have long been thought to be risk factors for gout. Similarly, the possibility that the consumption of dairy products has a role in protecting against gout has been raised by metabolic studies. We prospectively investigated the association of these dietary factors with new cases of gout. METHODS: Over a 12-year period, we prospectively examined the relationship between purported dietary risk factors and new cases of gout among 47,150 men who had no history of gout at base line. We used a supplementary questionnaire to ascertain whether participants met the American College of Rheumatology survey criteria for gout. Diet was assessed every four years by means of a food-frequency questionnaire. RESULTS: During the 12 years of the study, we documented 730 confirmed new cases of gout. The multivariate relative risk of gout among men in the highest quintile of meat intake, as compared with those in the lowest quintile, was 1.41 (95 percent confidence interval, 1.07 to 1.86; P for trend = 0.02), and the corresponding relative risk associated with seafood intake was 1.51 (95 percent confidence interval, 1.17 to 1.95; P for trend = 0.02). In contrast, the incidence of gout decreased with increasing intake of dairy products; the multivariate relative risk among men in the highest quintile, as compared with those in the lowest quintile, was 0.56 (95 percent confidence interval, 0.42 to 0.74; P for trend <0.001). The level of consumption of purine-rich vegetables and the total protein intake were not associated with an increased risk of gout. CONCLUSIONS: Higher levels of meat and seafood consumption are associated with an increased risk of gout, whereas a higher level of consumption of dairy products is associated with a decreased risk. Moderate intake of purine-rich vegetables or protein is not associated with an increased risk of gout.