Magnesium

Other name(s):

magnesium carbonate, magnesium citrate, magnesium hydroxide, magnesium oxide, magnesium sulfate

General description

Magnesium is an essential mineral. It helps more than 300 enzymes work. It’s needed for nerve and muscle activity. It also controls the electrical and muscle activity of the heart. Magnesium is in many antacids and laxatives. It's found in many foods. Because of this, magnesium deficiency is rare.

Magnesium is needed for many functions in the body. These include:

Activating enzymes that help break down carbohydrates
Nerve conduction
Helping control nerve irritability

Magnesium helps bone and tooth enamel form. It’s needed to convert protein, carbohydrates, and lipids into energy. It also helps make protein, RNA, and DNA. Magnesium helps break down (metabolize) many substances in the body.

Medically valid uses

Magnesium can be used as a laxative. This is often done in the form of magnesium sulfate or magnesium citrate. Magnesium citrate is given to cleanse the bowel before taking X-rays, CT scans, or MRIs of the abdomen.

It's used in some treatments for heartburn and upset stomach due to acid indigestion.

Magnesium is also used to prevent and treat low magnesium levels. This is called hypomagnesemia. In hospitals, magnesium is used to treat preeclampsia and eclampsia. These issues can happen in pregnancy and right after childbirth.

Magnesium works with calcium, vitamin D, and parathyroid hormone to make healthy bone tissue and tooth enamel.

Your healthcare provider may prescribe magnesium to treat certain heart problems. These include:

Heart attack
Heart rhythm problems
Heart failure
Digitalis poisoning

It may also be used during cardiac surgery.

Unsubstantiated claims

There may be benefits that have not yet been proven through research.

Magnesium may:

Help maintain health of muscles, bone, and nerve tissues
Help with anxiety and depression
Induce sleep in people with insomnia
Relieve premenstrual syndrome (PMS)
Prevent muscle cramps, muscle weakness, and fatigue
Prevent heart disease
Prevent hardening of the arteries (arteriosclerosis)
Prevent high triglyceride levels

Recommended intake

Magnesium is measured in milligrams (mg). The Recommended Dietary Allowance is RDA.

Group	RDA
Infants (0–6 months)	30 mg*
Infants (7 months to 1 year)	75 mg*
Children (1–3 years)	80 mg
Children (4–8 years)	130 mg
Children (9–13 years)	240 mg
Boys (14–18 years)	410 mg
Girls (14–18 years)	360 mg
Men (19–30 years)	400 mg
Women (19–30 years)	310 mg
Men (31 years and older)	420 mg
Women (31 years and older)	320 mg
Pregnant women (14–18 years)	400 mg
Pregnant women (19–30 years)	350 mg
Pregnant women (31 years and older)	360 mg
Breastfeeding women	No change

*Adequate Intake (AI)

Magnesium supplements come in many forms. Each form has a different amount of magnesium. Magnesium oxide and magnesium hydroxide have the highest amounts of it. Magnesium gluconate and magnesium gluceptate have the lowest.

Dose may be noted as the amount of magnesium. Or it may be noted as the percentage. Read the label to see how it is noted. You can learn the amount of elemental magnesium in a food. To do this, multiply the percentage of magnesium by 10. One (1) gram of magnesium oxide has 60.3% magnesium or 603 mg.

You should take magnesium supplements with food. This can help prevent diarrhea.

You may need more magnesium if you have any of these:

Diabetes
A malabsorption syndrome
Kidney disease
Take water pills (diuretics) regularly
Having vomiting or diarrhea
Have burns over large areas of the body
Extreme athletic activity
Moderate-to-heavy alcohol use

You may also need more magnesium if you are an athlete who restricts calories.

Food source	Nutrient content
Almonds, 1 oz.	80 mg
Spinach, boiled, 1 cup	78 mg
Cashews, 1 oz.	74 mg
Peanuts, ¼ cup	63 mg
Soy milk, plain or vanilla, 1 cup	61 mg
Black beans, cooked, ½ cup	60 mg
Yogurt, plain, low-fat, 8 oz.	42 mg
Kidney beans, ½ cup	35 mg
Banana, 1 medium	32 mg
Salmon, cooked, 3 oz.	26 mg
Milk, 1 cup	24 mg
Raisins, ½ cup	23 mg