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:
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
|
Magnesium is in nearly all foods. Because of this, it’s rare to have a diet low in
magnesium. Signs of deficiency may include:
Side effects, toxicity, and interactions
Taking too much magnesium can cause diarrhea. This is the most common side effect.
It can also cause:
Magnesium supplements may be dangerous for some people. This includes:
Women who are pregnant or breastfeeding should talk to their healthcare providers
before taking any supplements.
Magnesium is used in many antacid forms. These can cause diarrhea. Taking magnesium
with food may help prevent this side effect.
Magnesium may change the effects of some medicines. These include:
-
Antibiotics
-
Diuretics
-
Proton pump inhibitors
Tell your healthcare provider about all medicines you take before you take magnesium.