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Magnesium

By Shereen Jegtvig, About.com

Updated July 21, 2009

About.com Health's Disease and Condition content is reviewed by our Medical Review Board

whole grain bread

Whole grain bread contains much more magnesium than white bread.

Photo © Andre Lubbe
Definition:

Magnesium is a major mineral and is the fourth most abundant mineral in the human body. About half of the magnesium in your body is stored in your bones, while the rest is at work in the cells of your organs and other tissues.

Magnesium is required for hundreds of biochemical reactions to occur. It's crucial for normal muscle and nerve function, and helps maintain a regular health beat. You also need magnesium for strong bones and a healthy immune system.

Daily Requirements

Females

1 to 3 years: 80 mg per day
4 to 8 years: 130 mg per day
9 to 13 years: 240 mg per day
14 to 18 years: 360 mg per day
19 to 30 years: 310 mg per day
31+ years: 320 mg per day

Males

1 to 3 years: 80 mg per day
4 to 8 years: 130 mg per day
9 to 13 years: 240 mg per day
14 to 18 years: 410 mg per day
19 to 30 years: 400 mg per day
31+ years: 420 mg per day

Magnesium supplements may be beneficial for people who take certain medications that may cause loss of magnesium or reduce absorption, such as diuretics and antibiotics. Elderly people, alcoholics, people who have difficulty controlling diabetes, and individuals who suffer from inflammatory bowel disorders may all benefit from taking magnesium supplements. Magnesium supplements are safe, however megadoses may lead to diarrhea and cramping.

Dietary magnesium is found in dark green leafy vegetables, legumes, nuts, seeds and whole grains. Symptoms of magnesium deficiency are rare in healthy people.

Also Known As: magnesium oxide, magnesium sulfate, magnesium carbonate

Sources:

Dietary Supplement Fact Sheet: Magnesium. Office of Dietary Supplements. Accessed July 06, 2009. http://dietary-supplements.info.nih.gov/factsheets/magnesium.asp.

Dietary Reference Intakes. Food and Nutrition Board. Institute of Medicine. Accessed July 06, 2009. http://www.iom.edu/Object.File/Master/21/372/0.pdf.

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