Vitamin D (25 Hydroxy)

The Vitamin D test measures 25-Hydroxyvitamin D (25-OH Vitamin D), the most reliable indicator of the body’s Vitamin D status. It reflects Vitamin D obtained from sunlight exposure, diet, and supplements. Vitamin D is a fat-soluble vitamin that functions like a hormone, playing a vital role in calcium and phosphorus absorption, bone and teeth health, immune function, muscle function, cardiovascular health, mood regulation, and cell growth. Vitamin D is produced in the skin through UVB sunlight exposure, converted in the liver to 25-OH Vitamin D (the form measured in this test), and then activated in the kidneys to 1,25-dihydroxyvitamin D (Calcitriol). Despite abundant sunlight, Vitamin D deficiency is highly prevalent in India due to indoor lifestyles, skin pigmentation, clothing habits, and dietary factors, making this test a common component of routine health screening.

Who should get this test done?

This test is recommended for individuals who:

●     Experience fatigue, bone pain, muscle weakness, or unexplained body aches.

●     Have limited sun exposure.

●     Have or are at risk for Type 2 diabetes, autoimmune disorders, or cardiovascular disease.

●     Are children with delayed growth or signs of rickets.

●     Are taking Vitamin D supplements and require monitoring.

Why consider this test?

 Vitamin D testing is important because it helps:

●     Detect deficiency or insufficiency that may cause fatigue, bone pain, muscle weakness, and frequent infections.

●     Assess bone health, as low Vitamin D can lead to osteoporosis, osteomalacia, and rickets.

●     Evaluate immune function, with deficiency linked to infections and autoimmune conditions.

●     Investigate unexplained musculoskeletal symptoms such as muscle aches and weakness.

●     Monitor Vitamin D supplementation and ensure optimal levels are maintained.

More information

While Vitamin D deficiency is widely prevalent, excessively high levels due to unsupervised over-supplementation can lead to Vitamin D toxicity (hypervitaminosis D), characterized by hypercalcemia (excess calcium in the blood), nausea, kidney stones, and in severe cases, organ damage. Regular monitoring is essential for individuals on high-dose supplementation.

Other names:

●     25-Hydroxyvitamin D Test

●     25-OH Vitamin D Test

●     Calcidiol Test

●     Vitamin D3 Test

●     Serum Vitamin D Test

●     Cholecalciferol Test

●     Vitamin D - Total (D2 + D3)