[Medical Q&A] Is it better to supplement with more vitamin D?

Planner: Chinese Medical Association

Reviewer: Shang Xuejun, Chief Physician, General Hospital of Eastern Theater Command of PLA

This is not the case. Long-term excessive intake of vitamin D may lead to vitamin D poisoning, the clinical manifestations of which are mainly caused by hypercalcemia. The specific manifestations are as follows.

(1) Hypercalcemia: Excessive vitamin D in the body can lead to hypercalcemia, which is a condition where the calcium level in the blood is higher than normal. High levels of vitamin D can lead to increased calcium absorption by the body, which can cause a range of complications such as loss of appetite, mental confusion, high blood pressure, chest pain, irritability, and anxiety.

(2) Kidney damage: Too much vitamin D can cause kidney damage. This is because excessive vitamin D increases the calcium level in the blood, which can cause kidney damage. Patients with renal failure may experience hypercalcemia, hypercalciuria, or renal calcium deposition after taking vitamin D.

(3) Bone problems: Excessive vitamin D intake can lead to osteoporosis and brittle bones, with symptoms such as bone pain, severe back or joint pain, and increased risk of fractures. However, there is little evidence that high intakes of vitamin D are harmful for women of childbearing age and pregnant women. Harmful cases are mostly caused by misdiagnosis and excessive intake of vitamin D when preventing and treating rickets. Excessive exposure to sunlight does not lead to vitamin D poisoning.