What is the normal range for calcium levels in mg/dl?

The normal range for calcium levels in the blood is typically established to maintain proper physiological function, including muscle contraction, nerve transmission, and blood clotting. The correct range of 8.4-9.5 mg/dl indicates that this level is suitable for adequate metabolic activity and reflects a balance in calcium homeostasis within the body.

Levels that fall outside this range can indicate various health issues; for instance, low calcium levels (hypocalcemia) can lead to muscle spasms and cardiac issues, while high levels (hypercalcemia) can cause lethargy and kidney stones. Maintaining calcium within this normal range is essential for overall health, particularly in patients undergoing dialysis, where electrolyte imbalances can significantly affect treatment outcomes.

The other listed ranges do not accurately reflect the commonly accepted values for serum calcium levels, which is why they are not considered correct.