Vitamin D from sunlight in Iran
How long you need in the sun to make vitamin D, and when the sun is too low to make any at all, for 6 cities in Iran.
| City | Latitude | Elevation | Vitamin D winter |
|---|---|---|---|
| Tehran | 35.69°N | 1,178 m | 30 Nov – 17 Jan (49 days) |
| Mashhad | 36.30°N | 980 m | 27 Nov – 20 Jan (55 days) |
| Isfahan | 32.65°N | 1,578 m | none |
| Karaj | 35.83°N | 1,341 m | 30 Nov – 17 Jan (49 days) |
| Tabriz | 38.08°N | 1,396 m | 17 Nov – 30 Jan (75 days) |
| Shiraz | 29.61°N | 1,545 m | none |
The same sun that makes vitamin D also burns. UV index and sunburn times in Iran →