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RBC Magnesium

The RBC (Red Blood Cell) Magnesium test measures the concentration of magnesium within red blood cells, providing a more accurate reflection of magnesium levels inside the body’s cells compared to a standard serum magnesium test. Magnesium is a vital mineral involved in over 300 biochemical reactions in the body, playing a crucial role in nerve and muscle function, regulating blood pressure, supporting the immune system, and maintaining bone health. Why we need magnesium Magnesium is essential for energy production, protein synthesis, and maintaining normal muscle and nerve function. It also helps regulate heart rhythm, supports the immune system, and promotes healthy bones. Low magnesium levels can lead to a variety of health issues, including muscle cramps, fatigue, abnormal heart rhythms, and even seizures. Indications for testing - Muscle cramps or spasms - Fatigue or weakness - Abnormal heart rhythms (arrhythmias) - Migraines or chronic headaches - Difficulty managing blood pressure - Poor bone health or osteoporosis - Suspected magnesium deficiency due to malabsorption, chronic diseases, or medication use Doctors may recommend this test for patients with conditions like diabetes, gastrointestinal disorders, or kidney disease, or for those taking medications that affect magnesium levels, such as diuretics or proton pump inhibitors. Serum vs. RBC Magnesium A standard serum magnesium test measures the amount of magnesium circulating in the blood. However, only about 1% of the body's total magnesium is found in the blood serum, which can result in normal readings even when there’s a cellular magnesium deficiency. The RBC magnesium test offers a more accurate picture by assessing magnesium stored within red blood cells, where the majority of magnesium in the body is located. This makes it a better indicator of long-term magnesium status and intracellular deficiency. How to prepare There’s usually no special preparation required for an RBC magnesium test.

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