Most vitamins and all minerals are "essential nutrients", which means that they cannot be synthesized by the body and, therefore, must be consumed in the diet, either in the food eaten or supplementation taken.

Vitamins are classified in two categories:

1. Water soluble – Vitamin C and the eight members of the vitamin B complex
2. Fat soluble – Vitamins A, D, E, and K.

Minerals are classified in three categories:

1. Macronutrients – Essential minerals required in fairly large quantities (about 1 or 2 grams a day). They are calcium, chloride, magnesium, phosphorus (occurring mainly as phosphate in the body), potassium, magnesium, sodium, and sulfer.
2. Micronutrients – Essential minerals required in small amounts (usually called trace minerals). There are 15 trace minerals, including copper, fluoride, iodine, iron, selenium, and zinc. Except for fluoride, all of these minerals activate enzymes required in metabolism.

Note: Some trace minerals (micronutrients) such as arsenic, chromium, cobalt, nickel, silicon, and vanadium, which may be essential in animal nutrition, have not been established as requirements in human nutrition by the FDA. All trace minerals are toxic at high levels, and some (arsenic, nickel, and chromium) have been identified as causes of cancer at higher than normal levels within the body.

Chromium and vanadium have been proven beneficial for controlling blood sugar levels in some diabetics.

Some vitamins and minerals (such as vitamins C and E and selenium) act as antioxidants, as do other substances in fruits and vegetables (such as beta-carotene). Antioxidants protect cells against damage by free radicals, which are reactive byproducts of the normal activity of cells. Free radicals are thought to contribute to such disorders as heart disease and cancer. People who eat adequate amounts of fruits and vegetables, which are rich in antioxidants, are less likely to develop heart disease and certain cancers. However, whether these benefits are due to antioxidants, other substances in the fruits and vegetables, or other factors is not known.

It is also theorized that supplementation of too many antioxidants can create prooxidants, which can actually accelerate and promote damage by free radicals.

For more in-depth information about vitamins and minerals, visit MDsChoice.com.

Disclaimer: The information presented here is not a substitute for medical advice or treatment for specific medical conditions. You should seek prompt medical care for any specific health issues and consult your physician before starting a new fitness program.