Magnesium in biology

Magnesium in biology is a crucial element that plays a significant role in various biological processes. Magnesium is the eleventh most abundant element by mass in the human body and is essential to all cells and some 300 enzymes.

Function

Magnesium ions interact with polyphosphate compounds such as ATP, DNA, and RNA. Hundreds of enzymes require magnesium ions to function. Magnesium compounds are used medicinally as common laxatives, antacids (e.g., milk of magnesia), and in a number of situations where stabilization of abnormal nerve excitation and blood vessel spasm is required (e.g., to treat eclampsia).

Dietary sources, recommended intakes, and supplementation

Green vegetables such as spinach provide magnesium because the center of the chlorophyll molecule contains magnesium. Nuts (especially almonds and cashews), seeds, and whole grains are also good sources. In general, foods containing dietary fiber provide magnesium.

The Recommended Dietary Allowance (RDA) for magnesium varies depending on age and gender, but is generally around 300-400 mg/day. Magnesium dietary supplements are available, but it is best to obtain any needed vitamins and minerals through food, as excess supplementation can lead to side effects.

Deficiency

Magnesium deficiency (hypomagnesemia) is rare, but it can be caused by excessive alcohol consumption, prolonged diarrhea, malnutrition or high calcium intake. The symptoms are subtle and can include muscle cramps, fatigue, and irregular heartbeat.

Toxicity

Although magnesium is an essential nutrient, too much of it can be toxic. The most common symptoms of magnesium toxicity, also known as hypermagnesemia, are nausea and vomiting, reduced blood pressure, slowed heart rate, deficiencies of other minerals, and in severe cases, difficulty breathing and heart attack.

See also

• Minerals (nutrient)
• Dietary element
• Essential nutrient
• List of macronutrients
• List of micronutrients