Magnesium as Mineral – Rich Food Sources, Functions, Deficiency & Daily Requirements for Children, Men & Women

MAGNESIUM (Mg):

Magnesium is found both in intracellular and extracellular fluids. Total body magnesium is about 20 g, 75% of which is complexed with calcium in bone.

Source:

• Green vegetables, potatoes, almond, cheese, cereals, beans and almost all animal tissues.

Daily requirement:

• Adults : 350 mg
• Pregnant women : 450 mg
• Children: 150 mg. Serum level 0.7-1.0mmol/L.

Absorption:

• Absorption of magnesium takes place primarily in the small bowel by a specific carrier mechanism.
• Factors which increase the absorption of magnesium are vitamin D, PTH, high-protein intake, neomycin therapy.
• Factors which decrease the absorption are increased calcium intake, fatty acids, phytates and phosphate.

Functions:

• Involved in enzyme action. Magnesium is the cofactor of many enzymes requiring ATP. Alkaline phosphatase, hexokinase, fructokinase, adenylate cyclase, cAMP-dependent kinase need magnesium. Magnesium forms ATP-Mg2+ complexes and binds to the enzymes.
• Required in neuromuscular activity.
• An important constituent of bone and teeth
• Normal serum blood level is 2-3 mg/ dl (1-1.5mmol/l).

Clinical manifestations:

• Deficiency of magnesium causes muscular tremor, confusion, vasodilation and hyperirritability.

Hypermagnesaemia is observed in:

• Hypothyroidism
• Diabetic mellitus
• Acute renal failure

Hypomagnesaemia is seen in:

• Hyperthyroidism
• Chronic alcoholism
• Malnutrition
• Prolonged use of diuretics
• Portal cirrhosis   

Toxicity due to the increased use of magnesium-containing laxatives and antacids has been reported in the elderly. The chief symptoms are drowsiness, lethargy and weakness. 

Download More Information on Magnesium