Magnesium is necessary for nearly all biochemical processes in the body. It helps maintain muscle and nerve function, keeps the bones strong, controls the heart beat, and helps regulate blood pressure.
Magnesium is second most common intracellular cation, which is after potassium. Magnesium is a key element in more than 300 enzyme processes. Serum magnesium should be tested when a patient could have deficiencies such as malnutrition, alcoholism, diarrhea (more are included). Some deficiency symptoms of magnesium include muscle cramps, weakness, vertigo, depression.