Unlike minerals, vitamins are organic substances. Water soluble vitamins such as B and c must be taken regularly because the body cannot store these vitamins in significant amounts. The body can store excess amounts of fat-soluble vitamins such as A,D,E,and K, in its fatty tissues , sometimes for long durations of time. Scientists have discovered thirteen vitamins, five of these are produced in the body itself, people must get the others from either food and drink or supplements.One-a-day vitamins refer to multivitamins:supplements that contain various vitamins and, often, a number of minerals. The Food and Nutrition Board of the National Academy of sciences, sets the recommended Dietary Allowances(RDAs) for vitamins.The labels on vitamins supplements display a Daily Values(DVs) percentage. The FDA portions are based on 13 life stages, including children ages four to eight and males and females in the following age groups: nine to thirteen, fourteen to eighteen, nineteen to thirty, thirty-one to fifty, fifty-one to seventy, and older than seventy. To remove a supplement from the marketplace the FDA has to prove it to be …show more content…
Large doses of certain vitamins may also interfere with the absorption of other nutrients, reduce the effectiveness of some medications and cause false readings on lab tests. High doses of Calcium may reduce the absorption of iron. Too much vitamin E may increase the risk of bleeding in people taking blood-thinning medication. High levels of Vitamin C may produce false results in many different lab results, including blood tests and urine- glucose tests. Research suggests that taking doses above the minimum requirements can prevent or reduce the risk of some chronic diseases, including cancer and heart disease. Some scientists believe large amounts of certain antioxidant vitamins, such as vitamins A,C, and E, can prevent cell damage that may result in premature aging and degenerative, including Alzheimer 's disease, cancer, and heart disease. In 2003 a study by the U.S. Preventive Services Task Force, concluded, however, that there was little evidence to support the use of vitamin supplements to prevent cancer or heart disease. Most health experts agree that vitamins can not replace a healthy