Minerals and Nutritional Health
Most minerals are ingested in the form of complex molecules, some of which can be easily digested. For example, salt (sodium chloride) and monosodium glutamate can be broken down and the sodium released. In contrast, inorganic iron chemicals, e.g. iron oxide, are difficult to digest in the human gut, whereas iron-chemicals from meat, e.g. myoglobin and haemoglobin (in blood), are more easily digested but contain less iron.
Lack of essential minerals can cause nutritional diseases. Anaemia results from lack of iron, rickets from a deficiency of calcium in the diet or osteoporosis in older people. Calcium is needed for bone development, so both rickets and osteoporosis are diseases of the bones. Goitre occurs when the thyroid gland swells due to a lack of iodine, but this only really occurs where there is no iodine in the drinking water, or through thyroid diseases.
Approximate daily requirements for an adult of the main essential minerals are as below, where some of the minerals are shown as their ions. In addition, micro-amounts of chromium, cobalt, nickel, selenium and tin may also be needed, while fluorine (fluoride) is helpful for good development of children's teeth and may be supplemented in toothpaste or in the drinking water in some parts of the world.
|Mineral||Daily requirement/ grams||Good sources|
|Chloride||5.00||Salt as sodium chloride, some vegetables, seaweed, rye, tomatoes, lettuce, celery, olives|
|Potassium||3.50||Fruit – e.g. bananas, some vegetables - e.g. broccoli, parsnips and brussel sprouts, pulses, nuts and seeds, fish, shellfish, beef, chicken, turkey|
|Calcium||0.7||Milk, cheese and other dairy foods, green leafy vegetables – e.g. broccoli, cabbage and okra, but not spinach, soya beans, tofu, soya drinks with added calcium, nuts, bread and anything made with fortified flour, fish where you eat the bones – e.g. sardines and pilchards|
|Phosphorus (phosphates)||0.55||Red meat, dairy foods, fish, poultry, bread, brown rice, oats|
|Magnesium||0.27 - 0.30||Green leafy vegetables – e.g. spinach, nuts, brown rice, bread (especially wholegrain), fish, meat, dairy foods|
|Sodium||0.024||Ready meals, meat products – e.g. bacon, some breakfast cereals, cheese, some tinned vegetables, some bread, savoury snacks|
|Iron||0.0087 - 0.0148||Liver, meat, beans, nuts, dried fruit – e.g. dried apricots, wholegrains – e.g. brown rice, fortified breakfast cereals, soy flour, most dark-green leafy vegetables – e.g. watercress and curly kale|
|Manganese||0.005||Tea, bread, nuts, cereals, green vegetables – e.g. peas and runner beans|
|Copper||0.0012||Nuts, shellfish, offal|
|Zinc||0.0004 - 0.001||Meat, shellfish, dairy foods – e.g. cheese, bread, cereal products – e.g. wheat germ|
|Molybdenum||0.0005||Nuts, tinned vegetables, cereals – – e.g. oats, peas, leafy vegetables – e.g. broccoli and spinach, cauliflower|
|Iodide||0.00014||Seafish, shellfish, plant foods – e.g. cereals and grains|
- NHS (undated) Vitamins and minerals - Calcium, accessed 15 June 2016 
- NHS (undated) Vitamins and minerals - Iodide, accessed 15 June 2016 
- NHS (undated) Vitamins and minerals - Iron, accessed 15 June 2016 
- NHS (undated) Fluoride, accessed 15 June 2016 
- NHS (undated) Other vitamins and minerals, accessed 15 June 2016 
- Davidson, A. (1999) The Oxford Companion to Food, Oxford University Press. ISBN 0192115790.