Health
How to Get Vitamin D Without Burning
How much sun your skin actually needs to make vitamin D — and why supplementation often beats sun exposure.
Your skin makes vitamin D when UVB hits 7-dehydrocholesterol. The bad news: the same wavelengths cause sunburn and skin cancer. The good news: synthesis happens fast, and a tiny daily dose is enough.
How much sun is enough
For Fitzpatrick II–III at midday summer UV in mid-latitudes, ~10–15 minutes on face + arms produces ~1000 IU (Holick 2007). Darker skin needs 3–6× longer. North of ~37° latitude in winter, almost no UVB reaches the ground — sun is not a viable source.
- Type I–II: 8–15 min
- Type III: 15–25 min
- Type IV: 25–40 min
- Type V: 40–60 min
- Type VI: 60–90 min
Why supplements often win
A daily 1000–2000 IU vitamin D3 supplement (Endocrine Society 2011) avoids the cancer/photoaging cost entirely. The American Academy of Dermatology recommends getting vitamin D from diet and supplements rather than UV exposure.
Key takeaways
- Brief incidental sun is enough — no need to bake.
- Latitude and season matter a lot.
- Supplementation is the safer route for most people.