Vitamin D Test (25-Hydroxy) |#MTP|

Vitamin D plays an important role in calcium absorption and its deficiency can lead to abnormal bone development, bone weakness, and pain. It also helps maintain proper levels of calcium, phosphate, and parathyroid hormone. UV rays from the sun cause the skin to generate vitamin D in the body. Fish, eggs, and dairy products with added vitamin C are additional excellent vitamin sources. Vitamin D can be deficient due to sun exposure limitations or diet. To assess vitamin D levels, the 25-hydroxy vitamin D test measures the amount of calcidiol (the main form of stored vitamin D) in your blood. This test, also known as the 25-OH vitamin D test, helps diagnose deficiency or excess vitamin D, potentially linked to bone problems like rickets or osteoporosis.

Reasons for Undergoing the Vitamin D Test 

The vitamin D test is ordered for various reasons to assess and manage vitamin D levels in the body. Some key reasons include: 

• To check for symptoms of vitamin D deficiency, such as bone weakness, softness, malformation, fractures, muscle weakness, or cramps 
• For individuals at higher risk of vitamin D deficiency, including those over 65 years old, obese individuals, people with dark skin, those with limited sun exposure, and those with conditions like osteoporosis, celiac disease, Crohn's disease, or ulcerative colitis 
• To monitor vitamin D levels in people with chronic illnesses such as asthma, psoriasis, and certain autoimmune diseases 
• For individuals who have undergone gastric bypass surgery, which can affect vitamin D absorption 
• To evaluate if the diet is providing adequate vitamin D, especially in individuals who do not consume fortified foods or have difficulty absorbing fats 

List of Parameters Considered During the Vitamin D Test 

The primary parameter measured during a vitamin D test is the level of 25-hydroxyvitamin D (25(OH)D) in the blood. This measurement indicates: 

• Deficient levels: Below 12 nanograms per millilitre (ng/mL), indicating a deficiency that can lead to bone weakening, osteoporosis, and other health issues 
• Insufficient levels: Between 12 and 20 ng/mL, suggesting insufficiency that may not cause immediate symptoms but can lead to accelerated bone loss and increased fracture risk 
• Sufficient levels: Between 20 and 40 ng/mL (or sometimes up to 50 ng/mL), indicating adequate vitamin D levels with no known risks for health problems related to vitamin D 
• Toxic levels: Above 50 ng/mL, indicating toxicity, usually due to excessive supplement intake, leading to hypercalcemia and associated symptoms like fatigue, confusion, and kidney problems