Effects of vitamins C and E and β-carotene on the risk of type 2 diabetes in women at high risk of cardiovascular disease: a randomized controlled trial
Open accessAbstract
Background Vitamin 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.Objective The 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.Design In 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.Results During 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).Conclusion Our 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.
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Vitamin C supplementation had no effect on T2D risk during a median follow-up of 9.2 years in the Women's Antioxidant Cardiovascular Study.
“results from the Women’s Antioxidant Cardiovascular Study indicated that vitamin C supplementation had no effect on T2D risk during a median follow-up of 9.2 years.”
From Micronutrient Supplementation to Reduce Cardiovascular Risk (2022) · cites this paper as [31]
The Abstract reports a median follow-up of 9.2 years in the Women’s Antioxidant Cardiovascular Study. It reports no statistically significant overall effect of vitamin C on type 2 diabetes risk, but notes a trend toward reduced risk; saying supplementation “had no effect” is more definitive than the result supports. (LLM, conf=0.84)
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References 42 · Cited by 162
Research works printed but not linked: 4
- Vijayalingam S, Parthiban A, Shanmugasundaram KR, Mohan V. Ab- normal antioxidant status in impaired glucose tolerance and non- insulin-dependent diabetes mellitus. Diabet Med 1996;13:715-9.
- Polidori MC, Mecocci P, Stahl W, et al. Plasma levels of lipophilic antioxidants in very old patients with type 2 diabetes. Diabetes Metab Res Rev 2000;16:15-9.
- Food Nutrition Board, Institute of Medicine. Vitamin C. In: Reference dietary intakes for vitamin C, vitamin E, selenium, and carotenoids. Washington, DC: National Academy Press, 2000:95-185.
- Meydani M. Vitamin E. Lancet 1995;345:170-5.
- Authors
- Song, Y., Cook, N. R., Albert, C. M., Van Denburgh, M., & Manson, J. E.
- Affiliations
- Brigham and Women's Hospital (US)
- Corresponding author
- Song, Yiqing
- Venue
- The American Journal of Clinical Nutrition
- Publisher
- Elsevier BV
- Published
- 2009-08
- Volume
- 90
- Issue
- 2
- Pages
- 429-437
- ISSN
- 0002-9165 (ISSN-L)
- PMC
- PMC2848361
- OpenAlex
- W2169364927
- Cited by
- 162
- References
- 42
- Citations by year
- 2026: 1 · 2025: 4 · 2024: 7 · 2023: 9 · 2022: 14 · 2021: 4 · 2020: 9 · 2019: 7 · 2018: 2 · 2017: 7 · 2016: 13 · 2015: 10 · 2014: 10 · 2013: 12 · 2012: 17
- FWCI
- 11.38
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Licence
- Locations
- American Journal of Clinical Nutrition (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Institutes of Health
- BASF Corporation
- National Heart, Lung, and Blood Institute (HL 46959, R01HL046959)
- National Institute of Diabetes and Digestive and Kidney Diseases (L30 DK084809, K01DK078846)
- Topics
- Health Sciences › Medicine › Biochemistry › Antioxidant Activity and Oxidative Stress
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Nutritional Studies and Diet
- Health Sciences › Nursing › Nutrition and Dietetics › Vitamin C and Antioxidants Research
- Keywords
- type 2 diabetes, vitamin C, vitamin E, beta-carotene, antioxidant supplementation, oxidative stress, primary prevention of diabetes, cardiovascular risk factors
- MeSH terms
- Aged, Antioxidants, Ascorbic Acid, Cardiovascular Diseases, Diabetes Mellitus, Type 2, Double-Blind Method, Female, Follow-Up Studies, Humans, Middle Aged, Primary Prevention, Risk Factors, United States, Vitamin E, Incidence, Odds Ratio, Oxidative Stress, Risk Assessment, beta Carotene, Dietary Supplements
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