Minerals

Key points

• Minerals are nutrients that are needed in the body in tiny amounts.
• Minerals have many roles in the body.
• They form the architecture of bones, they are constituents of body fluids, they help enzymes to work, they help nerves to send signals.
• The amount of each mineral we need changes during our lifetime.

What are minerals?
Minerals are inorganic substances required by the body for a variety of functions including:
the formation of bones and teeth; as essential constituents of body fluids and tissues; components of enzyme systems; nerve function.

Some minerals are needed in larger amounts than others, e.g. calcium, phosphorus, magnesium, sodium, potassium and chloride. Others are required in smaller quantities and are sometimes called trace minerals, e.g. iron, zinc, iodine, fluoride, selenium and copper.

Despite being required in smaller amounts, trace minerals are no less important than other minerals.

Different foods supply different amounts of minerals. Eating a varied diet will help ensure an adequate supply of most minerals for healthy people.

Are mineral supplements necessary?
Although most people are able to meet their requirements for minerals (and vitamins) by eating a varied diet, there are certain groups of the population who have higher than normal requirements, e.g. the sick and those taking certain drugs. Also, women with high menstrual losses, may need to take iron supplements to avoid anaemia. Supplements may be prescribed by their doctor. Iron supplements are also sometimes given to pregnant women.

Supplements (especially if taken in an unsupervised manner) may cause mineral imbalances or have other side-effects; some minerals are toxic when taken in excess.
 
Further information
Henderson L et al (2003) The National Diet and Nutrition Survey: Adults Aged 19-64 years, Volume 3: Vitamin and Mineral Intake and Urinary Analysis. London, HMSO.

Department of Health (1991) Dietary Reference Values, A Guide. HMSO, London.

Joint Health Claims Initiative (2003) A list of well-established nutrient function statements, A report by the Joint Health Claims Initiative to the Food Standards Agency, Surrey, JHCI

© British Nutrition Foundation