A magnesium blood test is performed to measure magnesium levels in the blood and to monitor treatment efficacy of magnesium supplements. Magnesium is a mineral that plays an essential role in metabolism, nerve functioning, and maintenance of healthy bones. Its deficiency can cause symptoms such as muscle weakness, irregular heartbeats, and muscle twitch.
A level lower than the normal amount is called magnesium deficiency, it may be a sign of malnutrition and diabetes. If your results show a higher than normal amount of magnesium, it may be a sign of dehydration and kidney disease