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Magnesium - Red Cell


Magnesium is an important mineral needed for proper muscle, nerve, and enzyme function. It helps the body make and use energy and aids the movement of electrolytes such as potassium and sodium into and out of cells.

Red blood cell (RBC) magnesium is a measure of the magnesium in the red blood cells. Compared to serum magnesium, RBC magnesium is considered a more sensitive measure of magnesium in the body because when serum magnesium decreases, magnesium is pulled out of the red blood cells to stabilize the decrease. As a result, serum magnesium will remain normal even as magnesium levels in the tissue are decreasing and therefore RBC magnesium is a greater responsive indicator of the body’s magnesium levels.

What might a low result mean?

A low magnesium level (hypomagnesemia) can be caused by poor nutrition, high alcohol consumption, diarrhoea and an inability to absorb nutrients in the gut. Symptoms of low magnesium can include twitching or spasms, especially in the muscles of the face, nausea and vomiting as well as fatigue.

What might a high result mean?

The kidneys remove any excess magnesium from the body so developing raised magnesium levels (hypermagnesemia) is rare. However, people with kidney problems and those supplementing with high amounts of magnesium may be at risk of developing hypermagnesemia.

How might I improve my result?

If you are magnesium deficient, it is easy to improve your levels by incorporating more magnesium rich foods into your diet. The mineral is found in a wide variety of foods including green leafy vegetables, bananas, brown rice, whole grain bread, fish and dairy foods.