What Does "Low Magnesium" Mean?

“Low magnesium” refers to an abnormally low level of this mineral within the bloodstream. The level is regulated by the kidneys, but several disorders can result in a low amount. Magnesium plays an essential role in your health, and, as a result, low magnesium levels can cause a number of unpleasant symptoms.


Magnesium Basics

Magnesium is an electrolyte -- a mineral that has an electric charge. As explained in the “Handbook of Pathophysiology” by Elizabeth Corwin, Ph.D., only 1 percent of this mineral is in the bloodstream, because an estimated 49 percent is in the cells of the body and approximately 50 percent is stored in the bones. The cells use magnesium for a variety of biochemical reactions, to make DNA and protein, and to affect calcium and the muscles.

Magnesium Absorption and Metabolism

Women need 320 milligrams of magnesium each day, and, in most cases, 30 to 40 percent of this is absorbed in the small intestines. If you suffer from low magnesium, you might consume more of the magnesium you consume -- up to 70 percent. In a blood test, normal levels of magnesium range from 1.5 to 2.0 milligram equivalents per liter of fluid, according to F. Richard Bringhurst, M.D., senior vice president for medicine and research management at Massachusetts General Hospital in “Harrison’s Principles of Internal Medicine.”

Causes of Low Magnesium

Low magnesium -- also called hypomagnesia -- means having an abnormally low level of magnesium in the bloodstream. Several factors can cause low magnesium, but the most common reasons include malnutrition, vomiting, diarrhea, cirrhosis of the liver, alcoholism, and the inflammation of the pancreas, explains Gabor Kelen, M.D., chair of the Department of Emergency Medicine at John Hopkins University in “Tintinalli’s Emergency Medicine.” Some medications can cause a low magnesium level; cisplatin, some diuretics, cyclosporine, amphotericin and aminoglycosides.

Symptoms of Low Magnesium

People with hypomagnesemia may feel weak, nauseated and have to vomit. Because magnesium has a role in the normal functioning of the muscles, having a low magnesium level can lead to tremors, spasms, overactive reflexes and convulsions. A physician may be able to see abnormal activity on an EKG, or an electrocardiogram, that records heart activity. If the levels are very low, children can go into a generalized seizure, writes James Lewis, III, M.D., of Nephrology Associates in “The Merck Manual for Healthcare Professionals.”


This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.