Written by Marcia J. Egles, MD. In research with 46, 994 men who did not have gout their vitamin C intake was measured by a food frequency questionnaire. Those with the highest intake of vitamin C had a 45% lower risk of getting gout.
According to a recent study, Vitamin C may help prevent gout. Gout is the most common inflammatory arthritis in men, although it occurs in women as well. Gout is a treatable but burdensome disease. In gout, tiny crystals of uric acid can deposit in the joints, often at the base of the big toe, and cause sudden swelling with excruciating pain. Lifestyle changes which help lower uric acid levels in the blood may help prevent recurrent attacks of gout. The standard preventive measures against gout include avoiding alcohol and too much purine-rich meat. Obesity and high blood pressure are risk factors (1).
Several previous studies ( 2,3,4 ) have shown that higher vitamin C intakes can significantly increase uric acid excretion in the urine. Many of these studies used very high doses (over 3 grams) of vitamin C. In 2005, a randomized trial found that supplementation with vitamin C in a more moderate dose of 500 milligrams per day for two months reduced the uric acid levels in the blood (5). However, the relationship of lower uric acid levels to a lower risk of gout had yet to be demonstrated.
A new study now shows that higher vitamin C intakes in men may be associated with a lower risk of gout. From 1986 through 2006, the study followed the relation between vitamin C intake and the development of gout in 46,994 men who had never had gout previously. This study was part of the ongoing Health Professionals Follow-up Study. All the men were health caregivers with advanced educational degrees, such as physicians, dentists, pharmacists and veterinarians. They ranged in age from 40 to 75 years in 1986. The men were required to answer mail-in health questionnaires every four years. The rate of follow-up during the study exceeded 90%.
Food frequency questions were used to access vitamin C intake. Reports of gout were followed up by a special supplemental questionnaire. A sampling of the gout cases was further reviewed by a check of the subjects’ medical records.
During the twenty year follow-up, 1317 new cases of gout were documented. The risk of gout decreased with increased vitamin C intake. For example, those in the top vitamin C intake category of 1500 milligrams or more per day had a 45 per cent lower risk of gout as compared to those whose daily intake was less than 250 milligrams per day. (Relative risk was 0.55 with a 95% confidence interval; p value less than or equal to .001 for trend.) Nearly all the men who had daily vitamin C intakes of more than 500 milligrams took vitamin C supplements. For every 500 milligrams of vitamin C consumed, the risk of gout was reduced by about 15 per cent.
The study concluded that higher vitamin C intake was independently and strongly associated with a lower risk of gout. Given the general safety profile of vitamin C supplements, the researchers considered that vitamin C in the ranges observed in their study (dosages up to about 1500 milligrams per day) may be a useful option in the prevention of gout.
Source: Choi, Hyon K., Xiang Gao, and Gary Curhan. “Vitamin C intake and the risk of gout in men: a prospective study.” Archives of internal medicine 169.5 (2009): 502-507.
©2009 American Medical Association. All rights reserved.
Posted March 18, 2009.
References:
- Choi HK, Mount DB, Reginato AM. Pathogenesis of gout. Ann Intern Med. 2005;143(7):499-516.
- Mitch WE, Johnson MW, Kirshenbaum JM, Lopez RE. Effect of large oral doses of ascorbic acid on uric acid excretion by normal subjects. Clin Pharmacol Ther. 1981;29(3):318-321.
- Stein HB, Hasan A, Fox IH. Ascorbic acid-induced uricosuria: a consequence of megavitamin therapy. Ann Intern Med. 1976;84(4):385-388.
- Sutton JL, Basu TK, Dickerson JW. Effect of large doses of ascorbic acid in man on some nitrogenous components of urine. Hum Nutr Appl Nutr. 1983;37(2):136-140.
- Huang HY, Appel LJ, Choi MJ; et al. The effects of vitamin C supplementation on serum concentrations of uric acid: results of a randomized controlled trial. Arthritis Rheum. 2005;52(6):1843-1847.
