Magnesium benefits the body in a multitude of ways and is essential to good health. The fourth most abundant mineral in our body, about fifty to sixty percent of the body’s magnesium is found in our bones, with the balance in our muscle and other soft tissues. Magnesium helps maintain normal muscle and nerve function, regulates heart rhythm, supports a healthy immune system and keep bones strong. It also helps regulate blood sugar levels, promotes normal blood pressure and is involved in energy metabolism.
The daily recommended intake for magnesium is 400 mg for men 19 to 30 years of age and 420 mg for men over 30 years of age; 310 mg for women 19 to 30 years of age and 320 mg for women over 30 years of age. Cooper Clinic routinely tests magnesium levels as part of the blood profile in the comprehensive physical. A normal blood plasma level is 1.8 to 2.4 mg/dL.
Foods High in Magnesium
Foods that are naturally high in fiber generally have decent levels of magnesium. Dietary sources of magnesium include legumes, whole grains, vegetables (especially broccoli, squash, and green leafy vegetables), seeds and nuts (especially almonds and cashews). Other sources include dairy products, meats, chocolate and coffee. Per 3 ½ ounce serving, Kelp provides 760 mg magnesium, while almonds and cashews have approximately 270 mg, and pecans and English walnuts around 135 mg.
Magnesium and Digestion
The health status of our digestive system and kidneys influences our magnesium level. Primarily absorbed in the small intestine, magnesium is then transported through the blood to cells and tissues. Our kidneys excrete magnesium, so in instances where kidney health is impaired, too much magnesium may be expelled. In general, healthy individuals absorb about one-third to one-half of the magnesium ingested. Crohn’s disease and other gastrointestinal disorders can impair absorption of magnesium.
Magnesium Deficiency in Seniors
Older adults are at increased risk for magnesium deficiency. In addition to consuming less magnesium than younger adults, magnesium absorption decreases and renal excretion of magnesium increases in older adults. Seniors are also more likely to take drugs that interact negatively with magnesium. Magnesium supplements should not be taken at the same time as tetracycline or thyroid hormones – take either two hours before or after the medication.
Signs of Magnesium Deficiency
Early signs of magnesium deficiency could include loss of appetite, nausea, vomiting, fatigue, insomnia and weakness. Later signs may include numbness, tingling, personality changes, muscle contractions, cramps, seizures and abnormal heart rhythms. Because these symptoms are so broad, a magnesium deficiency can sometimes go undetected as physicians eliminate other issues.
Forms of Magnesium Supplements
Magnesium supplements combine magnesium with another substance such as a salt. Magnesium supplements include carbonate, chloride, gluconate, glycinate, hydroxide, oxide, silicate, stearate and sulfate. Epsom salts, often used to sooth a variety of skin conditions, is actually magnesium sulfate. Elemental magnesium refers to the amount of magnesium in each compound, and the amount of elemental magnesium in a compound and its bioavailability influence the effective of the magnesium supplement. Bioavailability is the amount of magnesium that is ultimately absorbed and useable by our body. In a more bioavailable form of magnesium, it is not unusual to find that four or more tablets are required to get to 500 mg of magnesium.
Article by Jill Turner, President Cooper Healthy Living
Nutritional Magnesium Association