Vitamin D (25 Hydroxy)

Who should get tested for Vitamin D, 25 - Hydroxyvitamin D, Serum?

Your healthcare provider may order Vitamin D test if you have symptoms of Vitamin D deficiency:

• Fatigue or tiredness
• Bone and back pain
• Muscle pain
• Depression
• Bone weakness
• Bone softness
• Bone malformation (in children)
• Fractures
• Hair loss
  
  

This test is also recommended for monitoring individuals on Vitamin D replacement therapy.

Risk factors leading to vitamin D deficiency

• Increased indoor lifestyles in cities – especially during the pandemic and work from home
• Food habits that limits dietary calcium and vitamin D intake – Vitamin D in foods is predominantly found in animal sources and hence vegetarians at higher risk
• Pollution can hamper synthesis of Vitamin D
• Wearing clothes that cover most of the skin
• Use of sunscreen

More about Vitamin D, 25 - Hydroxyvitamin D, Serum

Other names: 25-hydroxyvitamin D, 25(OH)D

Vitamin D is an essential nutrient for healthy bones and teeth. There are two forms of Vitamin D; D2 and D3. Vitamin D2 is found in fortified foods, dairy products and cereals while Vitamin D3 is produced by your body when you are exposed to sunlight. Vitamin D3 is also directly found in certain food sources like eggs, tuna and salmon etc. Both Vitamin D2 and vitamin D3 are converted to 25-hydroxyvitamin D in the liver and circulated in the bloodstream which can be measured by Vitamin D blood test.  

Why Vitamin D, 25 - Hydroxyvitamin D, Serum?

Vitamin D blood test measures the levels of 25-hydroxyvitamin D. If you are deficient in Vitamin D, then you are at risk of bone disorders, weakness, fatigue and fractures.

• Vitamin D is considered the most underdiagnosed and undertreated nutritional deficiency across the world. Vitamin D deficiency is seen both in countries that are sunshine deficient and sufficient.
• Different studies done in India over the last ten years have reported a prevalence of Vitamin D deficiency ranging from 50% to 94%.
• Despite being a tropical country with adequate sunshine throughout the year, vitamin D deficiency is high in India.
• Inadequate Vitamin D levels leads to poor absorption of calcium from diet thereby leading to calcium resorption from bone and kidney which affects bone and mineral density leading to osteoporosis, muscle weakness and increased risk of falls.
• Many studies have associated low Vitamin D concentrations with an increased risk of fractures and falls in older adults.
• In children too, Vitamin D deficiency leads to rickets and osteomalacia (soft bones).

Reference Values for Vitamin D, 25 - Hydroxyvitamin D, Serum

Interpretation

If you have low levels of Vitamin D, it means that you are not getting enough dietary vitamin D or not having enough exposure to sunlight. It could also means that there is a dysfunction in vitamin D absorption from food. Vitamin D levels is corrected through supplements, enriching diet sources or planned exposure to sunlight. Your doctor will guide you on the same.

We need to have just sufficient levels of Vitamin D in our body which means that excess is also a problem. A high level of vitamin D is likely due to excess pills or supplementation. Stopping the bills will correct the vitamin D levels.