There are two major groups
of non-caloric nutrients, but which are required for a healthy metabolism.
They are vitamins and minerals.
Vitamins are the classical
essential nutrients. Without a regular dietary supply, our body
will experience deficiencies that result in disease. The best known
example is probably gum disease when lacking vitamin C for an extended
period of time. Another example is Rickets, an underdeveloped bone
skeleton that is the result of vitamin D deficiency. This vitamin
is not strictly essential, as short exposure of the skin to sunlight
can provide enough vitamin D for adequate mineral absorption and
Minerals are salts that
have to be ingested and are found in various amounts in diverse
foods. Eating a rich diet of fruits, vegetables and meats (and dairy
products) always provides enough minerals for a healthy life. Minerals
play essential roles in all physiological processes and their benefit
cannot be easily reduced to single effects. The most prominent examples
of minerals are the role of calcium in bone strength, iron in blood
maintenance, and sodium in blood pressure regulation.