It’s used in more than 300 bodily functions. It has been linked to colon cancer prevention, a decreased risk of diabetes, modestly lowered blood pressure and improved brain function, and is essential for teeth and bone health. Despite this impressive pedigree, magnesium makes the list of the nation’s leading nutrient deficiencies. More than 50 percent of adults are not getting enough of the vital mineral, according to the National Center for Health Statistics.

How Much Do You Need?

Men 19–30 need 400 mg per day. Women in the same age range need 310 mg per day. For adults 31 years and older: men, 420 mg per day; women, 320 mg per day. There is no health risk associated with too much magnesium from natural food sources, because the kidneys eliminate any excess. But beware: Taking more than the recommended daily dose in supplement form may cause diarrhea, nausea and abdominal cramping.

Why Do You Need It?

Energy. Magnesium metabolizes energy when it reacts with adenosine triphosphate (ATP), a molecule that stores cellular energy. Studies show that low magnesium levels negatively affect athletic performance. Correcting magnesium deficiency can reduce fatigue and relieve insomnia.

Brain function. When synapses—connections between neurons—function correctly, the brain learns and retains information. Scientists agree that increasing brain magnesium prevents synapse loss and memory decline. There is also promising research that magnesium may restore cognitive function in Alzheimer’s patients.

Bone health. Nearly 60 percent of the body’s magnesium is found in bones. The nutrient, working in combination with calcium, is essential for bone development. Research links long-term magnesium deficiency to osteoporosis.

Why Aren’t We Getting Enough?

There are four main causes of magnesium deficiency: 1) Phosphates in carbonated beverages bind magnesium, making it unavailable to the body. 2) Chronic stress depletes magnesium stores. 3) Estrogen (used in birth control and hormone replacement therapy) prevents absorption. 4) Consuming more processed foods than whole foods high in nutrients. See our list below of magnesium-rich foods.

Did You Know?

Magnesium is more important than calcium in supporting bone health in children, according to a study from Baylor College of Medicine.

Magnesium-Rich Foods

Pumpkin seeds, roasted, ½ cup                  325 mg per serving

Lima beans, boiled, 1 cup                             126 mg per serving

Spinach, boiled, 1 cup                                   157 mg per serving

Black-eyed peas, cooked, 1 cup                   86 mg per serving

Almonds, dry-roasted, 1 ounce                    80 mg per serving

Shredded wheat cereal, 2 large biscuits    61 mg per serving

Edamame, cooked, shelled, ½ cup              50 mg per serving

Brown rice, cooked, ½ cup                           42 mg per serving

Low-fat yogurt, plain, 8 ounces                   42 mg per serving