Magnesium is a vitally important mineral for human health, and is one of the most abundant. Magnesium is necessary for a vast array of processes, including transfer, storage, and use of energy, metabolism of protein, fat, and carbohydrate, functional integrity of cell membranes, and parathyroid hormone regulation. Too-high or too-low levels of magnesium can disrupt the function of almost every organ, with potentially fatal consequences.
Magnesium can be found in high levels in many foods, including green vegetables, nuts, legumes, and grains. Other vegetables, fruits, and meat contain moderate levels of magnesium. Choosing fresh foods is essential for obtaining adequate dietary magnesium, however, as much of this vital mineral is lost during cooking and processing of food.
Magnesium Deficiency Causes
The main factors that control the availability of magnesium in the body are the amount that can be absorbed in the gastrointestinal tract (and therefore how much is obtained in the diet), and the amount that is excreted by the kidneys. Disruption in either of these two processes can cause magnesium deficiency.
- Inadequate dietary intake. For example, a diet high in processed foods and low in fresh foods may not provide enough magnesium.
- Gastrointestinal illness may affect the ability of the GI tract to absorb magnesium.
- Most magnesium that enters the kidneys as waste is filtered by the organs and recycled. Kidney malfunction caused by metabolic disorders and certain drugs can cause magnesium loss via excretion in the urine.
Symptoms of Magnesium Deficiency
Magnesium helps the body regulate blood levels of calcium and potassium. Therefore, some symptoms of low magnesium levels are also related to deficiencies in these minerals, as well as to deficiency of magnesium itself.
Possible symptoms of low magnesium levels include:
- Muscle weakness
- Muscle tremors
- Involuntary muscle contractions
- Tingling, prickling, or numb feeling of the skin
- Daytime drowsiness
- Loss of appetite
- Apathy, confusion, poor memory
Severe magnesium deficiency can cause hallucinations, delirium, rapid heartbeat, and cardiovascular changes. This degree of deficiency is very uncommon.
Medical Conditions Related to Magnesium Levels
Large-scale studies suggest that magnesium deficiency is associated with a wide range of diseases. The exact nature of the relationship is often difficult to pin down, however. For example, some studies have shown that adequate dietary intake of magnesium may have a protective effect on high blood pressure. However, the association is unclear because most foods that are high in magnesium are also high in dietary fiber and low in saturated fat. It is therefore thought that magnesium has only a modest role in reducing the risk of hypertension.
Other studies indicate that adequate daily intake of magnesium helps reduce the risk of cardiovascular disease and osteoporosis.
National Institute of Health Medline Plus: Magnesium in diet
Tibor Fulop, MD for eMedicine: Acid-Base, Fluid, and Electrolyte Disorders: Hypomagnesemia
Oregon State University Linus Pauling Institute: Micronutrient Information Center: Magnesium