Magnesium TestMagnesium testing measures your bloods magnesium levels, which are essential for muscle, nerve, and heart function, as well as energy production and blood pressure control. Low magnesium (hypomagnesemia) is more common than high levels, and deficiencies can be caused by conditions like malnutrition, alcoholism, and diabetes. Testing helps identify imbalances and guide treatment to prevent serious complications. Preparing for Your Sample Collection For