By Abhishek Singhh | Published on abhishekschauhan.com
As seen on: ANI News · Outlook Business · The Print · News X · The Tribune · MSN · The Daily Guardian
Your doctor runs a routine blood test. The report comes back. Vitamin D: deficient.
You are confused. You live in India. The sun rises at 6am and hits hard. You are not exactly hiding from it.
And yet here you are — alongside roughly 46% of the Indian population, deficient in the one nutrient your body is literally designed to make from sunlight.
This is not a coincidence. It is not bad luck. It is a systems failure. And the supplement industry’s response to it has made the problem worse, not better.
The Numbers That Expose the Paradox
A 2025 Metropolis Healthcare study analysed over 22 lakh test results collected between 2019 and January 2025 across India. The findings: 46.5% of Indians tested showed deficient vitamin D levels. A further 26% showed insufficient levels. That means nearly three in four Indians are not at optimal vitamin D status.
The ICRIER report (2025) puts it even more starkly: at least one in five Indians has vitamin D deficiency severe enough to affect health outcomes meaningfully. Among children aged 0–10, almost half showed signs of rickets. Among the elderly, 80–90% are at risk of osteoporosis linked to vitamin D insufficiency.
South India — one of the sunniest regions on the planet — recorded the highest deficiency rates at 51.6%.
Let that sit for a moment. The sunniest part of a country that gets year-round tropical sunshine has the worst vitamin D deficiency.
This is the paradox that most wellness content ignores because it complicates the simple “just go outside” advice that fills the internet.
Why Sunlight Alone Is Not Solving This
The body makes vitamin D through a photochemical reaction in the skin triggered by UVB radiation. This is well understood. What is less discussed is how many variables stand between you and that reaction actually working.
Skin pigmentation. Melanin — which gives Indian skin its colour — is a natural UVB filter. The same pigmentation that protects against skin cancer also reduces vitamin D synthesis efficiency. Darker skin requires significantly longer sun exposure to produce the same amount of vitamin D as lighter skin. This is not a flaw in Indian biology. It is a design trade-off that evolved for a different lifestyle — one that included spending hours outdoors, not 23 hours a day in offices, cars, and air-conditioned apartments.
Urban infrastructure. Glass blocks UVB. So does most clothing. The Indian urban professional who commutes in a car, works in a glass-and-concrete office, and spends evenings indoors can spend the entire day in a sunlit city and absorb almost no UVB whatsoever. The sun is visible. The UVB is not reaching the skin.
Air pollution. UVB radiation is scattered and absorbed by particulate matter in the atmosphere. In Delhi, Noida, Gurgaon, Mumbai, and most Indian tier-1 cities, pollution levels are high enough for a significant portion of the day that even outdoor exposure does not guarantee effective UVB transmission. The sun is technically out. The UVB is trapped above the smog layer.
Timing and angle. UVB synthesis is only effective when the sun is above 45 degrees above the horizon — roughly 10am to 3pm in most Indian cities. The morning walk at 7am and the evening stroll at 6pm that most health-conscious Indians rely on for their “sun exposure”? Nearly zero UVB. Good for mood, sleep, and circadian rhythm. Useless for vitamin D synthesis.
What Vitamin D Actually Does — and Why the Deficiency Matters
Vitamin D is not just a bone nutrient. That framing — left over from the early rickets research that identified the vitamin — has seriously underplayed what is now understood about its role in the body.
Vitamin D functions more like a hormone than a vitamin. It has receptors in virtually every tissue in the body. Its deficiency has been linked, across large population studies, to:
Immune dysfunction — including increased susceptibility to respiratory infections and autoimmune conditions. Given that India has some of the highest rates of tuberculosis globally, and vitamin D is known to play a role in immune defence against TB, this is not a minor detail.
Cardiovascular risk — including elevated blood pressure and arterial stiffness. India’s cardiovascular disease burden is already significant and worsening.
Insulin resistance and type 2 diabetes — India has the second-largest diabetic population in the world, and vitamin D deficiency is increasingly understood as a contributor to insulin resistance.
Depression and cognitive decline — the brain has vitamin D receptors. Deficiency in working-age adults correlates with mood dysregulation and cognitive fatigue. The urban professional who can’t focus and feels persistently low-grade exhausted may not need a productivity hack. They may need their vitamin D levels checked.
Muscle weakness and recovery impairment — relevant directly to the sleep and recovery crisis I wrote about last week. Poor vitamin D status compromises muscle repair and contributes to non-restorative sleep.
None of this means vitamin D deficiency causes all these conditions. The relationship is more complex — correlation with causation still being established in some areas. But the weight of evidence is clear enough that ignoring vitamin D status while addressing these symptoms is like trying to fix a car with a flat tyre by pressing harder on the accelerator.
How the Supplement Industry Gets Vitamin D Wrong
Here is where the conversation gets uncomfortable — because I formulate supplements, and I watch this category get butchered routinely.
Vitamin D supplementation in India is dominated by two problems: wrong form and wrong dose.
The form problem. There are two main forms of vitamin D supplement: D2 (ergocalciferol) and D3 (cholecalciferol). D3 is the form your skin naturally produces from sunlight. It is more bioavailable, more potent at raising blood levels, and more effective at maintaining those levels over time. D2 is cheaper to produce. Guess which one many budget Indian supplement brands use? If your supplement label says “Vitamin D” without specifying D3, verify before assuming.
The dose problem. India has no standardised national guideline for vitamin D supplementation doses — a gap the Indian Journal of Endocrinology and Metabolism’s 2025 expert consensus explicitly identified and attempted to address. In the absence of clear guidance, brands default to 400 IU or 600 IU doses — the old RDA figures set decades ago based on preventing rickets in children. These doses are not adequate to correct deficiency in an adult who is starting from a deficient baseline. The consensus of Indian endocrinologists now recommends maintaining physiological levels of 40–60 ng/mL — and reaching that from deficiency requires therapeutic doses, not maintenance doses.
The test-and-titrate gap. Vitamin D supplementation without knowing your baseline 25(OH)D levels is guessing. Some people are borderline insufficient and reach optimal levels with 1,000–2,000 IU daily. Others are severely deficient and need 4,000–5,000 IU daily for months to normalise. Selling a fixed-dose supplement to an unknown population and calling it a solution is marketing, not medicine.
The combination problem. Vitamin D is fat-soluble and requires co-factors to function correctly. Vitamin K2 directs calcium into bones and away from arteries — critically important when you are supplementing D3, which increases calcium absorption. Magnesium is required for vitamin D metabolism. Many Indian vitamin D supplements contain none of these co-factors and are sold as if the D3 capsule alone is sufficient. In isolation, high-dose D3 without K2 can potentially drive calcium into the wrong places. The co-factor story is not optional.
The Honest Protocol for Vitamin D in India
I am not writing prescriptions. But I can share what the evidence actually supports for an urban Indian adult who suspects deficiency:
Get tested first. A 25(OH)D blood test costs ₹600–1,200 at most labs. It is the only way to know whether you are deficient, insufficient, or already optimal. Supplementing without this number is guesswork.
If deficient (below 20 ng/mL): correcting deficiency requires a loading dose protocol — typically 60,000 IU once a week for 8–12 weeks, followed by maintenance. This requires a doctor’s involvement. This is not a supplement aisle decision.
If insufficient (20–30 ng/mL): 2,000–4,000 IU D3 daily, taken with a fat-containing meal for absorption, is a reasonable starting point. Re-test in 3 months.
If at maintenance (30–40 ng/mL) and aiming for optimal (40–60 ng/mL): 1,000–2,000 IU D3 daily with K2 (100–200 mcg MK-7 form) is well supported.
For sun exposure: 15–20 minutes of direct sun exposure on arms and legs between 10am–3pm, without sunscreen, on skin that is not behind glass. This will produce meaningful D3 in most people. Not a walk to the car. Direct midday exposure.
Diet is largely irrelevant here. Vitamin D from food (fatty fish, egg yolks, fortified dairy) is minimal compared to what the body can synthesise from sun or absorb from supplements. Dietary intervention alone will not fix deficiency.
The Bigger Picture India Is Missing
The ICRIER 2025 report explicitly notes that vitamin D deficiency threatens national productivity, diminishes workforce efficiency, and contributes to rising healthcare costs. This is a public health problem — not just a personal wellness question.
India spends less than 2% of GDP on public health. Vitamin D deficiency screening is not a national priority. Food fortification programmes exist but are inconsistently implemented. And in the supplement market, the products most prominently advertised for vitamin D are often the ones with the weakest formulations.
The urban professional who feels persistently tired, gets sick frequently, has lower back pain, and wakes up unrefreshed after a full night’s sleep is not necessarily failing at wellness. They may simply have untreated vitamin D deficiency — one blood test away from an answer, but surrounded by a market offering expensive supplements that won’t fix the problem, and public health infrastructure that doesn’t prioritise prevention.
That is the gap that honest wellness communication needs to address.
What to Do Right Now
If you have never tested your 25(OH)D levels — book a test this week. It is one of the highest-ROI health decisions you can make for under ₹1,000. If your levels come back deficient, see a doctor before starting supplementation. If insufficient, supplement thoughtfully: D3, not D2. With K2. With a fat-containing meal. At a meaningful dose.
Stop relying on your morning walk for vitamin D. It is not working. The sun at 7am in India does not produce UVB meaningful enough for synthesis. You are getting the circadian benefits of morning light — which are real and valuable — but not the vitamin D.
And if you are shopping for a supplement: check the form (D3, not just “vitamin D”), check the dose (1,000 IU minimum for maintenance), check for K2 on the label, and ask whether the brand can show you third-party lab results confirming what’s in the capsule matches what’s on the label.
India is sunny. India is deficient. These two facts coexist because the problem was never really about the sun.
This is part of an ongoing series on what India’s wellness industry gets wrong — and what the evidence actually says. Read the previous pieces: Why Your Supplement Is Lying to You and Indians Are Sleeping More Than Ever. So Why Are They Waking Up Exhausted?
Abhishek Singhh is the founder of Just What Works™ (Elara Biosciences), JeevRasa, The FarmPURE, ReEarthy, and SuppleFoods — five wellness brands built on one shared belief: the wellness industry has a honesty problem. He writes on supplement science, D2C brand building in India, and Ayurveda as a serious industry.
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Abhishek Singh is the founder of Just What Works and a passionate entrepreneur in the nutraceutical space. Through his brand and writing, he shares practical business strategies, wellness insights, and real-world lessons from his own startup journey. His work helps readers cut through noise and focus on building businesses — and lives — that truly work.