Background
Several metabolic studies and a recent double-blinded placebo-controlled randomized trial have shown that higher vitamin C intake significantly reduces serum uric acid levels. Yet, the relation with the risk of gout is unknown.
Methods
We prospectively examined over a 20-year period (1986–2006) the relation between vitamin C intake and the risk of incident gout in 46,994 male participants with no history of gout at baseline. We used a supplementary questionnaire to ascertain the American College of Rheumatology criteria for gout. Vitamin C intake was assessed every four years through validated questionnaires.
Results
During the 20 years of follow-up, we documented 1,317 confirmed incident cases of gout. Compared with men with vitamin C intake < 250mg/day, the multivariate relative risk (RR) of gout was 0.83 (95% confidence interval [CI], 0.71 to 0.97) for total vitamin C intake 500–999 mg/day, 0.66 (0.52 to 0.86) for 1,000–1,499 mg/day, and 0.55 (0.38 to 0.80) for ≥ 1500 mg/day (P for trend < 0.001). The multivariate RR per 500mg increase in total daily vitamin C intake was 0.83 (95% CI, 0.77 to 0.90). Compared with men who did not use supplemental vitamin C, the multivariate RR of gout was 0.66 (95% CI, 0.49 to 0.88) for supplemental vitamin C intake 1,000–1,499 mg/day and 0.55 (0.36 to 0.86) for ≥ 1500 mg/day (P for trend < 0.001).
Conclusions
Higher vitamin C intake is independently associated with a lower risk of gout. Supplemental vitamin C intake may be beneficial in the prevention of gout.