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[Antioxidants and health]
Leif H Skibsted1, Lars O Dragsted, Jørn Dyerberg
1Motions- og Ernaeringsrådets, Søborg. sm@meraadet.dk
Ugeskrift for Laeger
|September 1, 2006
Summary
The Danish Fitness and Nutrition Council found limited evidence to increase antioxidant recommendations for vitamins C and E. High-dose antioxidant supplements may pose health risks, and the benefits of fruits and vegetables are not linked to antioxidants.
Area of Science:
- Nutrition Science
- Dietary Recommendations
- Public Health
Background:
- The Danish Fitness and Nutrition Council reviewed current recommendations for antioxidant intake.
- Growing public interest in the health benefits of antioxidants necessitates a scientific evaluation.
Purpose of the Study:
- To assess the scientific basis for current and potential future recommendations regarding antioxidant intake.
- To evaluate the efficacy and safety of antioxidant supplementation, including vitamins C and E, polyphenols, and carotenoids.
Main Methods:
- Systematic review of scientific literature on antioxidant effects.
- Evaluation of evidence supporting increased intake levels for specific antioxidants.
- Assessment of potential health risks associated with high-dose antioxidant supplementation.
Main Results:
- Limited scientific basis exists for increasing recommended intake levels of vitamin C and vitamin E.
- Insufficient evidence supports recommendations for polyphenol or carotenoid supplementation.
- High-dose supplementation with vitamin E and beta-carotene may pose health risks.
- While a high intake of fruits and vegetables is linked to reduced lifestyle disease risk, this is not attributed to antioxidant effects.
Conclusions:
- Current evidence does not support increased recommendations for vitamin C and E intake.
- Polyphenol and carotenoid supplementation lack sufficient evidence for recommendation.
- High-dose antioxidant supplementation may be detrimental to health.
- The protective effect of fruits and vegetables against lifestyle diseases is not mediated by antioxidants.
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