Vitamin D Test Price, Reasons, Test Results

Vitamin D plays an important role in calcium metabolism and the maintenance of healthy bones and teeth. It has two important forms:-

Vitamin D2 : It is found in foods such as dairy items and cereals.

Vitamin D3 : It is synthesised by the human body (when exposed to sunlight). Some amounts of vitamin D3 are also found in certain foods, such as eggs and fatty fish (salmon, mackerel, etc.).

Both these forms are converted to a compound called 25-hydroxyvitamin D before the body can utilise them. The Vitamin D test measures the level of 25-hydroxyvitamin D in the bloodstream to determine total Vitamin D.

Abnormal vitamin D levels can be the various medical conditions, such as nutritional problems and bone disorders or bone damage.

Other names of the vitamin D are ergocalciferol (Vitamin D2), calcitriol (1,25-dihydroxyvitamin D), calcidiol (25-hydroxyvitamin D), calcifediol (25-hydroxyvitamin D) and Cholecalciferol (Vitamin D3).

Vitamin D test can be used as a screening test to monitor bone disorders and to check vitamin D levels in people with autoimmune conditions and chronic diseases like asthma.

Doctors generally recommend this test when they show the following symptoms of Vitamin D deficiency :-

• Fracture
• Weakening of bones.
• Deformity of bones in children
• Bone tenderness
• Breastfed infants are at higher risk of vitamin D deficiency if they do not take a vitamin D supplement.

In addition, this test is ordered if the following risk factors for Vitamin D deficiency are observed :-

• Difficulty absorbing fats from foods.
• Dark complexion in old age.
• Bone marrow disorders, such as osteoporosis
• Decreased sun exposure.
• Obesity
• Have gone through Gastric bypass surgery in the past.

No special preparation is required for the Vitamin D test.

A lab technician withdraws about 3 ml of blood from a vein in arm by inserting a needle. The blood sample is collected in a vial or test tube, which is then sent to a laboratory for analysis.

The whole process takes about 5 minutes.

There is no risk associated with this test. Although some people experience minor bruising or slight pain at the site of the blood draw, most symptoms soon disappear. If any discomfort is felt, be sure to check with a doctor as soon as possible.

Most laboratories use the same reference range, even though the method used for the vitamin D test varies among laboratories.

Normal Result

Since vitamin D poisoning is rare, the focus of this test is to determine the lower limit of total 25-hydroxyvitamin D 25-hydroxyvitamin D (d2 + d3), which would indicate vitamin D deficiency.

According to the US Institute of Medicine, 25-hydroxyvitamin D levels of 20 ng/ml or higher are essential for bone health.

Abnormal Result

The following are the conditions associated with abnormal 25-hydroxyvitamin D levels :-

• less than 20 ng/mL – this level indicates deficiency of Vitamin D. 
• 21 to 29 ng/ml – this level range indicates insufficiency of Vitamin D. 

A low level of 25-hydroxyvitamin D in the bloodstream may indicate the following :-

• Lack of sun exposure
• Insufficient dietary vitamin D intake
• Problems with absorption of vitamin D from the gut

Some drugs can also affect the production of 25-hydroxyvitamin D in the liver. An elevated blood level of 25-hydroxyvitamin D may indicate the use of additional nutritional supplements or vitamin pills.