Vitamin C Intake and Serum Uric Acid Concentration in Men

XIANG GAO; GARY CURHAN; JOHN P. FORMAN; ALBERTO ASCHERIO; HYON K. CHOI

Abstract

Objective

We examined associations between vitamin C intake and serum uric acid in men in a population-based study.

Methods

We included 1387 men without hypertension and with body mass index (BMI) < 30 kg/m² in the Health Professional Follow-up Study. Dietary intake was assessed with a semiquantitative food frequency questionnaire validated for use in this population. Serum uric acid concentrations were measured.

Results

Greater intakes of total vitamin C were significantly associated with lower serum uric acid concentrations, after adjustment for smoking, BMI, ethnicity, blood pressure, presence of gout, use of aspirin, and intake of energy, alcohol, dairy protein, fructose, meat, seafood and coffee. An inverse dose-response association was observed through vitamin C intake of 400–500 mg/day, and then reached a plateau. Adjusted mean uric acid concentrations across total vitamin C intake categories (< 90, 90–249, 250–499, 500–999, or ≥ 1000 mg/day) were 6.4, 6.1, 6.0, 5.7, and 5.7 mg/dl, respectively (p for trend < 0.001). Greater vitamin C intake was associated with lower prevalence of hyperuricemia (serum uric acid > 6 mg/dl). Multivariate odds ratios for hyperuricemia across total vitamin C intake categories were 1 (reference), 0.58, 0.57, 0.38, and 0.34 (95% CI 0.20–0.58; P for trend < 0.001). When we used dietary data, which were assessed 4–8 years before blood collection, as predictors, we observed similar inverse associations between vitamin C intake and uric acid.

Conclusion

These population-based data indicate that vitamin C intake in men is inversely associated with serum uric acid concentrations. These findings support a potential role of vitamin C in the prevention of hyperuricemia and gout.

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Footnotes

X. Gao, MD, PhD, Research Associate, Department of Nutrition, Harvard University School of Public Health; G. Curhan, MD, ScD, Department of Epidemiology, Harvard University School of Public Health, Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School; J.P. Forman, MSc, MD, Instructor in Medicine, Harvard Medical School, Associate Physician, Renal Division, Brigham and Women’s Hospital; A. Ascherio, MD, DrPH, Associate Professor, Department of Nutrition and Department of Epidemiology, Harvard University School of Public Health, Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School; H.K. Choi, MD, ScD, Associate Professor, Department of Medicine, Vancouver General Hospital, University of British Columbia.
Supported by TAP Pharmaceuticals and NIH/NINDS grant R01 NS048517.
- Accepted for publication February 4, 2008.