• Yiqing Song, Nancy R Cook, Christine M Albert, Martin Van Denburgh, and JoAnn E Manson.
• Division of Preventive Medicine and Cardiology Division, Harvard School of Public Health, Boston, MA 02215, USA. ysong3@rics.bwh.harvard.edu
• Am. J. Clin. Nutr. 2009 Aug 1;90(2):429-37.

BackgroundVitamin C, vitamin E, and beta-carotene are major antioxidants and as such may protect against the development of type 2 diabetes via reduction of oxidative stress.ObjectiveThe purpose of this study was to investigate the long-term effects of supplementation with vitamin C, vitamin E, and beta-carotene for primary prevention of type 2 diabetes.DesignIn the Women's Antioxidant Cardiovascular Study, a randomized trial that occurred between 1995 and 2005, 8171 female health professionals aged > or =40 y with either a history of cardiovascular disease (CVD) or > or =3 CVD risk factors were randomly assigned to receive vitamin C (ascorbic acid, 500 mg every day), vitamin E (RRR-alpha-tocopherol acetate, 600 IU every other day), beta-carotene (50 mg every other day), or their respective placebos.ResultsDuring a median follow-up of 9.2 y, a total of 895 incident cases occurred among 6574 women who were free of diabetes at baseline. There was a trend toward a modest reduction in diabetes risk in women assigned to receive vitamin C compared with those assigned to receive placebo [relative risk (RR): 0.89; 95% CI: 0.78, 1.02; P = 0.09], whereas a trend for a slight elevation in diabetes risk was observed for vitamin E treatment (RR: 1.13; 95% CI: 0.99, 1.29; P = 0.07). However, neither of these effects reached statistical significance. No significant effect was observed for beta-carotene treatment (RR: 0.97; 95% CI: 0.85, 1.11; P = 0.68).ConclusionOur randomized trial data showed no significant overall effects of vitamin C, vitamin E, and beta-carotene on risk of developing type 2 diabetes in women at high risk of CVD. This trial was registered at clinicaltrials.gov as NCT00000541.

35 keywords...

hide…