The short explanation
Sunlight helps the skin make vitamin D, but how much you make depends on the time of day, the season, where you live, your skin tone and how much skin is uncovered. There is no single exact time that suits everyone. Sunlight through a closed glass window does not help much, because glass blocks most of the type of sunlight that makes vitamin D. Short periods outdoors with arms or legs uncovered, in the late morning to early afternoon when the sun is higher, are more effective than early morning sun. Darker skin needs more time than lighter skin for the same effect.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Many people who work indoors, wear covered clothing, live in polluted cities or have darker skin still have low vitamin D despite living in a sunny country.
- Too much sun increases the risk of sunburn and skin damage, so short regular exposure is better than long periods.
- Foods such as egg yolk, oily fish and fortified milk or oils contain some vitamin D, but diet alone often does not provide enough. If your level is low, your doctor may suggest a supplement.
- If you cannot get outside during working hours, a short walk at lunch or time on a terrace or balcony on weekends with forearms uncovered can help. Sunscreen reduces vitamin D production, but protecting your skin from burning still matters.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This answer cannot tell whether your vitamin D is low or how much sunlight you need. A blood test and your doctor's advice can guide that.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Should I get my vitamin D level checked?
- How much sun exposure is realistic and sensible for me?
- Do I need a supplement?
- Should my calcium also be checked?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Book an appointment soon
- See a doctor within a few days if you have bone pain, muscle weakness that makes climbing stairs or getting up from the floor hard, or cramps and tingling in your hands and feet.
Raise it at a routine appointment
- Book a routine appointment if you have bone pain, muscle weakness or tiredness and want your vitamin D checked.
Sources
The evidence this explanation is built on.
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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