Vitamin D Deficiency in India: Do You Really Need That Test?

Almost every Indian who gets a vitamin D test seems to come back “low”. Studies using the global cut-off find vitamin D deficiency in roughly two out of three Indians, and sometimes far more. But a growing group of doctors now says the number on your report may not mean what you think, and that most healthy adults don’t need the test at all.

So who should test, how much sun actually helps, and when do supplements make sense? The surprising part is the threshold on your lab report, and section 2 explains why it may not fit Indian bodies.

How Common Is Vitamin D Deficiency in India?

It depends a lot on how you measure it. A systematic review published in Cureus in January 2026 pooled Indian studies from 2010 to 2024. Using the global cut-off of under 20 ng/mL, it found deficiency in about 67% of people, with individual studies ranging from 40% to 90%.

That’s odd for a sunny country. India gets plenty of sunshine, and yet report after report says “deficient”. There are real reasons some Indians run low: darker skin, indoor jobs, covering most of the skin outdoors, and in north India, winter fog and pollution.

Why winter makes it worse in the north

In a recent explainer in The Week, Dr Sudhir Kumar of Apollo Hospitals noted that winter fog and air pollution can substantially reduce UVB, especially in northern India. UVB is the part of sunlight your skin uses to make vitamin D. So a smoggy Delhi winter afternoon gives you less than the same hour in Chennai.

The Catch: Your Lab Report’s Cut-Off May Not Fit Indians

The Cureus review argues the 20 ng/mL cut-off was “originally developed for North American populations”. The authors say skin pigment, low calcium in Indian diets and other body chemistry make it a poor fit here.

They point to a gap: very high “deficiency” rates on paper, but nothing like the same level of rickets or fractures you’d expect if 67% of people were truly short. They propose a lower cut-off of 12 ng/mL and note that ICMR-NIN has suggested lowering the definition of deficiency to under 12 ng/mL.

Testing has exploded

The review also cites a New Delhi hospital study of 26,339 vitamin D tests from 2008 to 2016, showing a threefold rise in yearly test volume. The authors argue this reflects misapplied thresholds more than new disease.

The review has its own weaknesses, including some citations that don’t line up with its reference list. So read it as a strong argument from Indian researchers, not the final word.

Also readAlways Tired? It Could Be Vitamin B12 Deficiency (Signs to Check)

Who Actually Needs a Vitamin D Test?

The Endocrine Society, a large international body of hormone specialists, updated its advice in 2024. According to the American Academy of Family Physicians’ summary, it advises against routine vitamin D testing in healthy people, because there’s no evidence-based target level to aim for.

Testing may be reasonable if you have:

• Low blood calcium (hypocalcaemia).
• Problems absorbing nutrients, such as after gastric bypass surgery or with inflammatory bowel disease.
• Kidney conditions where the body loses more vitamin D, like nephrotic syndrome.
• Medicines that break vitamin D down faster, which your doctor can check.

Dr Kumar made the same point in The Week: routine testing of every healthy person isn’t recommended, and testing fits better when there’s a clinical reason like unexplained bone pain or chronic kidney or liver disease.

How Much Sun Do You Need for Vitamin D?

There’s no magic number of minutes, and anyone who gives you one is guessing. Dr Kumar says there’s no universal “15–20 minute” prescription, partly because darker skin needs more UV to make the same amount of vitamin D.

The best time of day

An Indian study from Tirupati, described in a 2018 letter in the Indian Journal of Endocrinology and Metabolism, found the best conversion to active vitamin D between 11 am and 2 pm. It was a lab model, not human skin, but it matches what we know about UVB being strongest around midday. The same letter mentions a Delhi study where outdoor workers with long sun exposure were vitamin D-sufficient.

Practical sun habits for Indian life

• Take a short walk or sit on the balcony or terrace in late morning with your arms and face uncovered.
• In north Indian winters, use clearer, sunnier days. Fog and smog cut UVB.
• Don’t stay in strong midday sun for long periods. Dr Kumar warns against it, and the NHS advises covering up or using sun protection during long spells in the sun.
• Morning sun is still good for your body clock and mood, even if it makes less vitamin D.

Also readWhy Do We Feel Lazy in Winters? Know the Reason Behind It!

Supplements: How Much Is Safe?

The NHS vitamin D page recommends 10 micrograms (400 IU) a day for adults and children over one. It also says people with darker skin, including those of south Asian background, may not make enough from sunlight and should consider a supplement all year.

The upper limit matters

The NHS says adults and children aged 11 to 17 shouldn’t take more than 100 micrograms (4,000 IU) a day. Children aged 1 to 10 shouldn’t go above 50 micrograms (2,000 IU). Taking too much for a long time can raise calcium in the blood (hypercalcaemia), which can weaken bones and damage the kidneys and heart.

Two things often surprise people:

1. You can’t overdose on vitamin D from the sun. The NHS says so plainly. Toxicity comes from supplements.
2. Higher doses may be right for some groups, but only with a doctor’s guidance. The Endocrine Society suggests empiric supplementation for children and teenagers, pregnant people, adults over 75 and people with high-risk prediabetes. For healthy adults aged 19 to 74, it suggests doctors consider not routinely recommending supplements, because no clear health benefit has been shown.

Food Sources and Everyday Habits

Food alone rarely covers vitamin D, but it helps. The NHS lists oily fish, red meat, egg yolks and fortified foods like some cereals and spreads. Liver is also a source, but the NHS says pregnant people should avoid it.

For vegetarians, options are narrower. Check packs of milk, edible oil and breakfast cereals for “fortified with vitamin D” on the label, and lean more on sun habits.

A simple winter plan

• Get outside for a short walk in late morning on most days, more on clear days.
• Eat eggs or fish a few times a week if you eat them, and pick fortified foods if you don’t.
• Ask your doctor about a supplement if you’re pregnant, over 75, mostly indoors or have a condition that affects absorption.
• Skip routine tests if you’re healthy and have no symptoms.

Feeling tired all the time? Don’t assume it’s vitamin D. Low B12, poor sleep and anaemia are also common causes. Our guide on why we feel lazy in winter covers the other suspects.

This article is for information only and is not medical advice. Please consult a doctor before starting vitamin D supplements or if you have bone pain, a chronic illness or are pregnant.

Frequently Asked Questions

What level counts as vitamin D deficiency?

Most labs flag under 20 ng/mL as deficient, using a cut-off developed for North American populations. A 2026 Indian review argues a lower cut-off of 12 ng/mL may fit Indians better, and says ICMR-NIN has suggested the same. Ask your doctor how to read your report.

What is the best time to get sunlight for vitamin D in India?

An Indian lab study found the best vitamin D conversion between 11 am and 2 pm. Short exposure of your face and arms in late morning is a practical habit. Avoid long periods in strong midday sun.

Can I take vitamin D tablets without a test?

The NHS suggests a low daily dose of 10 micrograms (400 IU) is reasonable for people with darker skin, including south Asians. Higher doses should only be taken with a doctor’s advice, and adults shouldn’t exceed 4,000 IU a day.

Do I need a vitamin D test if I feel tired?

Not automatically. Tiredness has many causes, including low B12, anaemia and poor sleep. Guidelines link vitamin D testing to specific reasons, like unexplained bone pain or kidney, liver or gut conditions, so let your doctor decide which tests make sense.

Can too much sun cause vitamin D overdose?

No. The NHS says you can’t overdose on vitamin D from sunlight; too much comes from supplements. Still cover up or use sun protection during long spells in strong sun to protect your skin.

The Bottom Line

Vitamin D deficiency in India is partly a real problem and partly a measuring problem. For most healthy adults, the fix isn’t another test or a big sachet. It’s sun on your arms in late morning and a sensible diet.

Building a winter health routine? Pair this with our guides on winter immunity foods and peanuts in winter.

Sources

• Cureus (2026): vitamin D deficiency in India and population-specific reference standards
• AAFP: Endocrine Society guideline on vitamin D for prevention of disease
• NHS: vitamin D
• Indian Journal of Endocrinology and Metabolism: exposure to sunlight and vitamin D synthesis (2018)
• The Week: how much sunlight do you need for vitamin D (11 Oct 2026)