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The Vitamin Update

Quick guide to Magnesium

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Essential For

  • production and transfer of energy
  • a healthy heart, bones, muscles and blood vessels
  • protein and carbohydrate metabolism
  • transport of substances across cell membranes
  • manufacture of genetic material

Absorption and metabolism
About 50 per cent of dietary magnesium is absorbed.

Deficiency
Symptoms include fatigue, mental and heart problems. Marginal deficiency may lead to cardiovascular disease, hypertension, diabetes, osteoporosis, asthma, migraine, PMS and kidney stones.

Sources
These include whole grains, nuts and green vegetables.

Daily recommended dietary intakes
Men (under 30) - 400mg Men (over 30) - 420 mg Women (under 30) - 310 mg Women (over 30) - 320 mg Pregnancy (14 to 18) - 400 mg Pregnancy (19 to 30) - 350 mg Pregnancy (over 30) - 360 mg Lactation (14 to 18) - 360 mg Lactation (19 to 30) - 310 mg Lactation (over 30) - 320 mg

Toxic effects of excess intake
Symptoms include skin flushing, nervous depression and fatigue.

Therapeutic uses of supplements
These include treatment of stress, fatigue, cardiovascular disease, migraine, kidney stones, asthma, premenstrual syndrome, osteoporosis, muscle cramps, pre-eclampsia and diabetes.

Interactions
Calcium and magnesium act together in many body functions. Alcohol, diuretics, antidepressants, estrogen and heart drugs can increase requirements.

Cautions
Magnesium supplements should not be used by those who have impaired kidney function or serious heart disease.

Read the full guide