One of the great medical discoveries of the last century involved the identification of the nutritional substances necessary for life. Along with the “macronutrients” (fat, carbohydrate, and protein), these “micronutrients” make up the essential ingredients of a healthful diet.

Vitamins and minerals have been available as supplements since at least the 1930s. In the 1960s, however, a new way of using them came into vogue: so called “megadose" therapy. The megadose approach involves taking supplements at doses far above nutrition needs in the hopes of producing a specific medical benefit—essentially, using nutrients as natural drugs. 1 Each individual supplement article in this database explains what is known about the potential risks and benefits of megadose therapy.

The original (and still important) method of using nutrients involves taking them at around the level of nutrition needs. This method may be considered nutrition insurance for the majority of us who don’t get all the nutrients we need from foods. For information on which nutrients may be worth taking on a daily basis, see the Nutritional Support article .

Finally, there are a number of substances sold as supplements that are not in fact nutritional in nature. While they might offer health benefits, you don’t need them to stay alive. Examples include the following:

  • Isoflavones – chemicals found in soy that may reduce the risk of cancer and some forms of heart disease
  • Glucosamine – a substance found in gristle that’s useful for osteoarthritis
  • Melatonin – a hormone not found to any great extent in foods, but that is helpful for sleep
These substances are also described in the individual supplement articles in this database .

Specific Supplements

This database has articles on all major supplements. For detailed information, see the herb and supplement index page .


REF1 Bratman S, Girman A. Mosby’s Handbook of Herbs and Supplements and their Therapeutic Uses. St. Louis, MO: Mosby, Inc.;2003.