Then why do so many people swear by vitamin supplements?
"One of the most common reasons why people take vitamin and mineral supplements is because they believe that supplements will prevent the development of chronic diseases including cardiovascular disease, cancer, and Alzheimer’s. But the evidence accumulated so far in large clinical trials indicates, overall, that supplements do not prevent most chronic diseases. In fact, in some cases, supplements can be harmful."
Are there any supplements that are actually worth taking?
"Vitamins are essential to life and health, but we can get vitamins and minerals from a varied, balanced diet. Supplements can be useful in certain circumstances (vitamin D supplements in subjects with very low levels, antioxidant supplements in patients with macular degeneration), but these uses should be guided by a doctor."