How much magnesium should you take each day? Because magnesium is essential to over 300 biochemical reactions in the body, it's important to fulfill your needs. While the short answer is that the average healthy adult needs between 270 and 400 mg of magnesium per day, depending on their weight, it's useful to take a deeper look at all the factors involved.
Why You Need Magnesium
Magnesium is the fourth most prevalent mineral in the body and is essential to the function of every organ in the body. Magnesium plays a role in muscle and nerve function, regulating heart rhythms, promoting a heathy immune system, and bone health. It is also a key ingredient in protein synthesis, regulating blood sugar levels, and maintaining normal blood pressure. Researchers are also interested in studying magnesium as a treatment for diabetes, cardiovascular disease, and hypertension.
Sources of Magnesium
Your body absorbs between one-third and one-half of the magnesium you consume. Foods rich in magnesium include green leafy vegetables, whole grains, legumes, nuts, seeds, and halibut. While a healthy varied diet should provide you with all the magnesium you need, most people in the Western world don't consume enough magnesium. While low blood magnesium levels are common, clinical magnesium deficiency is rare in the industrialized world.
Clinical magnesium deficiencies are relatively rare in the Western world, but certain people are more at risk for them. Temporary magnesium deficiencies can be caused by illnesses or behaviors that cause vomiting or diarrhea. Serious chronic magnesium deficiencies are usually caused by behaviors or illnesses that inhibit the body's ability to absorb magnesium or maintain normal blood magnesium levels. The most likely culprits are irritable bowel syndrome, Crohn's disease, diabetes, kidney disease, and alcoholism.
Because hypermagnesemia, or the presence of too much magnesium in the blood, can cause serious side effects, including death, physicians recommend that you do not take magnesium supplements unless directed to by your doctor. No level of magnesium supplementation for infants is considered healthy without physician supervision. Children between the ages of one and three should not take more than 65 mg of unsupervised supplemental magnesium per day. Children between the ages of three and eight are limited to 110 mg per day. Adults and pregnant or lactating women should not take more than 350 mg of supplemental magnesium a day unless directed to by their doctor.