Vitamin D from sunlight in China
How long you need in the sun to make vitamin D, and when the sun is too low to make any at all, for 11 cities in China.
| City | Latitude | Elevation | Vitamin D winter |
|---|---|---|---|
| Shanghai | 31.22°N | 12 m | none |
| Beijing | 39.91°N | 49 m | 3 Nov – 15 Feb (105 days) |
| Shenzhen | 22.55°N | 4 m | none |
| Guangzhou | 23.12°N | 15 m | none |
| Chengdu | 30.67°N | 499 m | none |
| Tianjin | 39.14°N | 11 m | 6 Nov – 12 Feb (99 days) |
| Wuhan | 30.58°N | 20 m | none |
| Dongguan | 23.02°N | 1 m | none |
| Daxing’anling | 52.33°N | 348 m | 22 Sep – 1 Apr (192 days) |
| Heihe | 50.24°N | 139 m | 28 Sep – 25 Mar (179 days) |
| Jiagedaqi | 50.42°N | 381 m | 29 Sep – 25 Mar (178 days) |
The same sun that makes vitamin D also burns. UV index and sunburn times in China →