Minerals are inorganic substances which constitute about 4% of the total body weight. They are concentrated most densely in the skeleton.
They can be divided up into:
- those present in relatively large amounts e.g.:
- sodium
- potassium
- calcium
- magnesium
- chlorine
- phosphorous
- sulphur
- trace elements: minerals present at a concentration of less than 50mg/kg e.g. selenium
- essential minerals essential to growth or health e.g. sodium, selenium
Minerals may interact with each other on a variety of levels:
- as co-factors in enzymes, they modulate the substrate/product relationship of biochemical pathways
- as ions across membranes, they contribute to:
- the state of electrical excitability, e.g. the action potential
- the distribution of fluid volumes between compartments
- competitive interactions e.g. of zinc and copper for absorption
- as common targets for regulatory compounds e.g. vitamin D's action on calcium, phosphate and magnesium