RBC Magnesium Unit Converter

RBC magnesium measures the amount of magnesium inside your red blood cells. This provides a better picture of your body's true magnesium stores compared to a standard serum magnesium test.

Only about 1% of the body's magnesium circulates in the blood. The remaining 99% is stored in bones (50-60%), muscles, and soft tissues. Because the body tightly regulates blood levels by drawing magnesium from these stores, serum levels can appear normal even when the body is deficient.

By measuring magnesium within the red blood cells themselves, the RBC test can detect deficiency earlier than serum testing, making it useful when symptoms suggest low magnesium but serum levels appear normal.

Magnesium is obtained entirely from the diet and absorbed through the small intestine and colon. About 50-60% is stored in bones, with the remainder distributed in muscles, soft tissues, and cells throughout the body.