What are vitamins and minerals?

The discovery of vitamins was one of the great advances in nutrition of the 20th century. Vitamins are organic dietary compounds, which unlike the macro-nutrients, are not metabolised to provide energy. Furthermore vitamins (for the most part) cannot be manufactured by the body and therefore must be derived from food.

Each vitamin performs several specific functions or is required to prevent an associated deficiency disease. Vitamins tend to be categorised by virtue of whether they are fat or water-soluble (this parallels the non essential and essential groupings). The fat-soluble vitamins are A, D, E and K, as they remain in the body it is possible to build up body stores and therefore they are non essential but similarly intake should be monitored in order to avoid excess. The B vitamins (except B12) and C are water-soluble hence it is essential that regular intake is maintained in order to avoid deficiency.

Minerals - What are they?

Sixteen minerals have been identified as being essential if the body is to function properly, in all these minerals account for only 3-4% of the weight of the human body. We derive our minerals from the food we eat but the body can maintain its own mineral balance over short periods. If mineral intake is too low the body will use amounts stored in the muscles, the liver and if necessary the bones. If a mineral intake is too high the excess is typically excreted - overdose is unlikely. Minerals are essential to body structure: bones, teeth, etc. They are also essential for the conduction of nerve impulses which keep the heart beating or the eyes blinking. Vitamins and minerals form only a small percentage of the nutrients we eat but they are involved in every function the body performs.

The wide diversity of supplements available reflects the fact that individuals have different requirements: men versus women, active versus sedentary, pregnant versus menopausal, children versus adolescents, etc.

Combinations may be more useful than a single supplement e.g. calcium and vitamin D, iron and vitamin C, etc. Certain vitamin and minerals work in synergy. Vitamin D for example, helps the absorption of calcium; similarly vitamin C enhances the uptake of iron. In these and indeed many other cases it is beneficial to take a combination rather than a single nutrient supplement. 

Herbs and plant extracts

Herbs have been used for hundreds of years and are considered to be the basis of modern pharmacology. A number of herbs need to be used with caution however, but in general there tend to be fewer side effects when using herbal medicine as compared with the use of modern synthetic drugs.