Harvard Health Letter

What you should know about: Magnesium

Many Americans take magnesium supplements, which are sometimes marketed as super pills that help a long list of ailments including muscle tension, low energy, and trouble sleeping. But think twice before you reach for this mineral in pill form. "The main reason to take this is a documented low body magnesium, usually identified by a low blood level," says Dr. Bruce Bistrian, chief of clinical nutrition at Beth Israel Deaconess Medical Center and professor of medicine at Harvard Medical School.

Magnesium amounts in food

1 ounce dry roasted almonds

80 milligrams

½ cup frozen spinach (cooked)

78 milligrams

¾ cup bran flakes cereal

64 milligrams

1 medium baked potato w/skin

48 milligrams

½ cup canned kidney beans

35 milligrams

Function

Magnesium is one of the body's most abundant minerals and is an important part of hundreds of functions, including maintaining muscle and nerve function, as well as a steady heartbeat, healthy immune system, and strong bones.

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