Antioxidants

Summary

Antioxidants are man-made or natural substances that may prevent or delay some types of cell damage. Antioxidants are found in many foods, including fruits and vegetables. They are also available as dietary supplements. Examples of antioxidants include:

• Beta-carotene
• Lutein
• Lycopene
• Selenium
• Vitamin A
• Vitamin C
• Vitamin E

Vegetables and fruits are rich sources of antioxidants. There is good evidence that eating a diet with lots of vegetables and fruits is healthy and lowers risks of certain diseases. But it isn’t clear whether this is because of the antioxidants, something else in the foods, or other factors.

High-dose supplements of antioxidants may be linked to health risks in some cases. For example, high doses of beta-carotene may increase the risk of lung cancer in smokers. High doses of vitamin E may increase risks of prostate cancer and one type of stroke. Antioxidant supplements may also interact with some medicines. To minimize risk, tell your health care providers about any antioxidants you use.

NIH: National Center for Complementary and Integrative Health

Start Here

• Antioxidant Supplements: What You Need To Know National Center for Complementary and Integrative Health
• Antioxidants Harvard School of Public Health
• Antioxidants: Protecting Healthy Cells Academy of Nutrition and Dietetics
• Antioxidants: What You Need to Know American Academy of Family Physicians

Related Issues

• Antioxidants and Cancer Prevention National Cancer Institute
• Coenzyme Q10 National Cancer Institute
• Red Wine and Resveratrol: Good for Your Heart? Mayo Foundation for Medical Education and Research

Statistics and Research

• Chocolate Health Claims: Sweet Truth or Bitter Reality? National Institutes of Health

Clinical Trials

• ClinicalTrials.gov: Antioxidants National Institutes of Health

Specifics

• Coenzyme Q10 Mayo Foundation for Medical Education and Research
• Cranberry National Center for Complementary and Integrative Health
• Grape Seed Extract National Center for Complementary and Integrative Health
• Noni National Center for Complementary and Integrative Health
• Selenium National Institutes of Health, Office of Dietary Supplements
• Vitamin A National Institutes of Health, Office of Dietary Supplements
• Vitamin C National Institutes of Health, Office of Dietary Supplements
• Vitamin E National Institutes of Health, Office of Dietary Supplements
• Zinc National Institutes of Health, Office of Dietary Supplements

Find an Expert

• Find a Nutrition Expert Academy of Nutrition and Dietetics
• Food and Nutrition Information Center Food and Nutrition Information Center
• National Institutes of Health, Office of Dietary Supplements National Institutes of Health, Office of Dietary Supplements

Journal Articles

• Antioxidants