Magnesium (Mg)
Definition
Magnesium keeps the muscles, nerves and heart working properly and helps control blood pressure and blood sugar. It is important for building strong bones and supports the immune system. As an electrolyte, it regulates fluid balance and pH.
Purpose
For symptoms such as muscle cramps, irregular heartbeat, fatigue or numbness. Also for monitoring conditions that affect magnesium (kidney disease, diabetes, alcohol use disorder) or medications that do (diuretics, some antibiotics).
Results
- Low, inadequate intake, absorption problems (such as Crohn's disease), kidney problems or excessive loss through chronic diarrhea
- High, usually excessive supplementation or medications; the most common cause is kidney failure. Also dehydration and hypothyroidism
Normal Values
Laboratory specific.
Risks and Limitations
Important limitation:
The amount of magnesium in your blood can be normal even when the amount of magnesium stored in your body is low.
In other words, a normal blood magnesium does not mean that the body's stores are adequate. For a more accurate assessment, a urine magnesium or red blood cell (RBC) magnesium test may be ordered.