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Six macrominerals are required by people in gram amounts. Four (Na, K, Ca, and Mg) are cations; two (Cl and P) are accompanying anions (see Fluid Metabolism). Daily requirements range from 0.3 to 2.0 g. Bone, muscle, heart, and brain function depend on these minerals.
Nine trace minerals (microminerals) are required by people in minute amounts: chromium, copper, iodine, iron, fluorine, manganese, molybdenum, selenium, and zinc. (For sources, functions, effects of deficiency and toxicity, and dietary requirements, see Table 1: Mineral Deficiency and Toxicity: Trace Minerals and Table 2: Mineral Deficiency and Toxicity: Guidelines for Daily Intake of Minerals.) All trace minerals are toxic at high levels; some minerals (arsenic, nickel, and chromium) may be carcinogens.
Mineral deficiencies (except of iodine, iron, and zinc) do not often develop spontaneously in adults on ordinary diets; infants are more vulnerable because their growth is rapid and intake varies. Trace mineral imbalances can result from hereditary disorders (eg, hemochromatosis, Wilson's disease), kidney dialysis, parenteral nutrition, or restrictive diets prescribed for people with inborn errors of metabolism.
Last full review/revision August 2008 by Larry E. Johnson, MD, PhD
Content last modified August 2008
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