A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.

An alkaline earth metal, Magnesium is important for many biochemical functions and reactions; for bone and muscle function, protein and fatty acid formation, activation of B vitamins, blood clotting, insulin secretion, and ATP formation. More than 300 enzymes require magnesium for catalytic action. The adult daily requirement is about 300 mg/day. Magnesium is found in many green plants, vegetables, and seeds; chlorophyll is a magnesium-centered porphyrin compound. Magnesium salts are used for magnesium deficiency supplementation. (NCI04)

In medicine, a mineral used by the body to help maintain muscles, nerves, and bones. It is also used in energy metabolism and protein synthesis.

Light, silvery metallic element, symbol Mg, atomic number 12; its salts are essential in nutrition, being required for the activity of many enzymes especially those concerned with oxidative phosphorylation.

Magnesium is one of the major intracellular cations. For normal neuromuscular activity, humans need normal concentration of extracellular calcium and magnesium.