Also known as: A-beta-carotene, carotenes, carotenoid, provitamin A.
Potential uses: Beta carotene possibly decreases the risk of some cancers, and helps reduce the rate of macular degeneration (when the central part of the retina starts to deteriorate) and increase heart health.
Usual dose: Beta carotene supplements (beyond what you get from food) are not recommended for the general population. If you eat 5 servings of fruits and vegetables a day, you'll get 6 to 8 milligrams of beta carotene, which is enough.
Are there any risks? Beta carotene is considered safe when consumed in foods as part of a balanced diet. But high doses of supplements can make your skin turn yellow or orange and may cause an increase in damage caused by free radicals to the body.
What does the research show? In women with breast cancer, diets high in vegetables and fruits that contain the full range of carotenoids (not just beta carotene alone) have been associated with reduced recurrence of breast cancer. There is no evidence that supplements contributed to the protective effect. More studies are needed.