Overview of Magnesium's Role in the Body

ByJames L. Lewis III, MD, Brookwood Baptist Health and Saint Vincent’s Ascension Health, Birmingham
Reviewed/Revised Sep 2023
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Magnesium is one of the body's electrolytes, which are minerals that carry an electric charge when dissolved in body fluids such as blood, but the majority of magnesium in the body is uncharged and bound to proteins or stored in bone. (See also Overview of Electrolytes.)

Bone contains about half of the body’s magnesium. Blood contains very little. Magnesium is necessary for the formation of bones and teeth and for normal nerve and muscle function. Many enzymes in the body depend on magnesium to function normally. Magnesium is also related to the metabolism of calcium and the metabolism of potassium. To maintain a normal level of magnesium in the blood, adults need to consume 310 to 420 milligrams of magnesium a day.

The level of magnesium in the blood depends largely on how the body obtains magnesium from foods and excretes it in urine and stool and less so on the total body stores of magnesium. The level of magnesium in the blood can become

More Information

The following English language resource provides information that may be useful. THE MANUAL is not responsible for the content of this resource.

  1. National Institutes of Health Office of Dietary Supplements: Magnesium Fact Sheet for Consumers: provides a general overview of magnesium, including its role in the body and daily nutrition requirements

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