The mount of magnesium present in the body is less than that of calcium and phosphorus. About 20-30gms of it are found in an average adult. Sixty per cent of it fund on bone surfaces in the form of phosphates and carbohydrates. The remaining magnesium is found in the body cells, extracellular fluids and blood serum. A very small portion of it is bound to protein.
The dietary absorption of magnesium is about 40%. A high calcium intake increase increases the requirement for the magnesium as well. Excess is excreted from the kidneys. The unabsorbed magnesium from the diet is excreted in the faeces.
Magnesium is required for all living cells It is catalyst for numerous biological reaction involving the release of energy. It is a constituent of bone. It is essential for normal metabolism of calcium and phosphorus. This mineral activates some enzymes responsible for the break–down of glycogen. Its presence in extracellular regulates the transmission of nerve impulses.
Flour and cereal products, dry beans, soya beans, peas and nuts are good sources of magnesium. Green leafy vegetables are excellent sources of it because magnesium is a part of chlorophyll.
The dietary intake of magnesium to maintain balance is about 350 mg day. Magnesium content of food is generally much higher than calcium. A diet based on cereals, pulses generally much higher than calcium. A diet based on cereals, pulses and vegetables provides adequate magnesium to meet the daily needs.
Effect of imbalances
Under normal condition of health and food intake magnesium deficiency does not occur. A deficiency of it may result from mal absorption syndrome, chronic alcoholism, toxemia of pregnancy or after intake of diuretics. Deficiency of magnesium give rise to neuromuscular irritability, titanic convulsions, twitching tremors, convulsions. Taken is excess it result in extreme thirst, excessive heat in the body, decrease in neuromuscular movements.