Vitamin D deficiency is widespread in India despite the climate, because of indoor work, covering clothing, air pollution, sunscreen and skin pigmentation. It affects bone, muscle, immune function and mood, and it is inexpensive to test and correct.
Why the sun is not enough
Vitamin D synthesis needs direct UVB on bare skin, and several common factors interrupt it.
Darker skin requires substantially longer exposure than lighter skin for the same synthesis. Urban air pollution filters UVB before it reaches ground level. Most working days are spent indoors, and the exposure that does occur is often through glass, which blocks UVB entirely. Clothing that covers most of the skin, and sunscreen, both reduce it further — and neither is a reason to stop.
The result is a country with abundant sunshine and prevalence figures that consistently surprise people.
Is this what is happening to you?The two-minute check further down asks four questions and shows the result immediately. No email, no call.
Take the 2-minute checkWhat it affects beyond bone
Vitamin D receptors are present in most tissues, which is why the symptom picture is broad and rarely specific.
- Bone mineralisation, and calcium absorption — calcium intake achieves much less without it
- Muscle function and strength, which is why deficiency shows up as aches and weakness
- Immune regulation, relevant to both infection and autoimmune conditions
- Mood, with an association to low mood that is consistent if not fully explained
2-minute check
Why are you so tired?
Four questions. Fatigue nearly always has a findable cause.
How much do you sleep, and how well?
Any hair fall, breathlessness on stairs, or heavy periods?
Do you crash in the afternoon?
Any low mood or difficulty concentrating?
No obvious driver from these answers
If it persists, thyroid, ferritin and vitamin D are the sensible first tests.
There are likely contributors here
Ferritin, thyroid and vitamin D between them explain most persistent fatigue.
Several contributors appear to be present
This is worth testing properly rather than pushing through. All three common causes are treatable.
This check is an indication, not a diagnosis. It does not replace medical advice.
Testing and correcting
The test is 25-hydroxy vitamin D and it is inexpensive. Testing before supplementing is worth doing, because doses vary widely and because vitamin D is fat-soluble and can accumulate.
Correction is usually a loading regimen followed by maintenance, and the regimen should come from your doctor rather than from a website. Very high doses bought over the counter are not a better version of the same thing.
- Sunlight: fifteen to thirty minutes on arms and face, mid-morning, several times a week — adjusted for skin tone
- Food: fortified milk, egg yolk, fish. Indian diets supply very little, and this cannot be corrected by food alone
- Magnesium sufficiency, which is needed for vitamin D to be activated
- Retest after correction rather than assuming it has worked
A note on what it does not do
Vitamin D has been proposed as a solution to a very wide range of problems, and the evidence is considerably stronger for correcting a deficiency than for supplementing someone who is already sufficient.
We will recommend testing, and correction where a deficiency exists. We will not recommend high-dose supplementation on the general principle that more is better, because for a fat-soluble vitamin that principle is wrong.
In short
Questions we are asked
How long in the sun do I need?
Fifteen to thirty minutes on exposed arms and face, several times a week, mid-morning. Darker skin needs considerably longer. Through glass it does not count.
Can I get enough from food?
Not from a typical Indian diet. Fortified milk, egg yolk and fish contribute, but correcting an established deficiency through food alone is not realistic.
Reading about it is the easy part.The assessment turns this into your own numbers — free, with a free first consultation, and no figure quoted that we cannot substantiate.
Start my free assessmentConditions this relates to
Recipes that put this into practice
Palak and lemon dal
The lemon at the end is not a garnish. It is what makes the iron usable.
See the recipe →Flaxseed chutney
Whole flaxseed passes through undigested. Ground into a podi, it becomes a daily habit.
See the recipe →Turmeric and black pepper preparation
The pepper is not a garnish. Without it, most of what you drink is not absorbed.
See the recipe →Related reading
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The stall is not a failure of discipline. It is a predictable physiological response.
Read →What an anti-inflammatory diet can and cannot do for joints
The honest version is narrower than the marketing version, and more useful.
Read →References
- Indian Academy of Pediatrics — revised guidelines on prevention and treatment of vitamin D deficiency.
- Endocrine Society — clinical practice guideline on vitamin D deficiency.
- [Further references to be completed by the medical review panel.]
This article is general health information, written by a clinical nutritionist and reviewed by a doctor. It is not a diagnosis and it does not replace advice from your own clinician. Never change prescribed medication on the basis of what you read here.