Vitamin D Deficiency: Signs, Tests and What To Do
Despite year-round sunlight, Vitamin D deficiency is widespread in India — driven by indoor lifestyles, air pollution, sunscreen use and clothing that covers most skin. Because the symptoms are vague, it often goes unrecognised for years.
It is also one of the most straightforward nutritional problems to test for and correct.
Why so many people are deficient
Vitamin D is synthesised when skin meets sunlight, but the UVB rays needed are often filtered by glass, pollution and haze, and most working hours are spent indoors. Diet contributes little on its own, since few foods contain meaningful amounts naturally.
That combination leaves a large share of the population running low, often without dramatic symptoms.
The signs that get overlooked
No single symptom confirms deficiency, but a cluster should raise suspicion.
- Persistent fatigue and low energy despite adequate sleep
- Diffuse bone aches and muscle weakness, especially in the legs
- Low mood, or feeling flat for no clear reason
- Frequent minor infections or slow recovery
- Hair fall that resists the usual explanations
Who is at higher risk
Some groups are tested more readily because their risk is higher.
- People who work indoors or rarely expose skin to sun
- Older adults, whose skin synthesises Vitamin D less efficiently
- People with darker skin tones, who need longer sun exposure
- Those who are overweight, or have absorption issues
- Anyone with a history of fragility fractures or low bone density
The test is simple
A 25-hydroxy Vitamin D blood test measures your true stores and is the standard check. It needs no fasting and can be collected at any time of day, which makes home sample collection particularly convenient.
Your report gives a value in ng/mL, generally read as deficient, insufficient or adequate depending on the range your laboratory uses.
How repletion actually works
Correction is usually straightforward but should follow a proper schedule rather than ad-hoc supplementation. Deficiency is commonly treated with a higher weekly dose for a defined period, then reduced to a maintenance dose.
Because Vitamin D is fat-soluble and accumulates in the body, more is not better — mega-doses taken continuously can reach toxic levels. The right approach is to test, treat to a target, and re-test to confirm.
A note on sun and food
Regular, sensible sun exposure helps maintain levels, but it is rarely enough to correct a documented deficiency on its own. Fatty fish, egg yolk and fortified foods contribute modestly.
When a test shows a clear deficiency, supervised supplementation is far more reliable than trying to lift the number through sunlight alone.