Vitamin D Basics
Most humans depend on sun exposure for vitamin D as very few foods naturally contain it[1].
{?|for most people with light skin, 10-30 minutes of midday sun on arms and legs 2-3 times per week is sufficient - darker skin requires more time due to melanin blocking UV}
{?|people at higher latitudes, those who cover most skin, elderly individuals, and those with dark skin often cannot get enough vitamin D from sun alone and may need 800-1000 IU daily}
Sunscreen Facts
Myth: Sunscreen causes vitamin D deficiency
Reality: Regular sunscreen use does not compromise vitamin D status in healthy people[2].
Reality: Regular sunscreen use does not compromise vitamin D status in healthy people[2].
Regular daily sunscreen use reduces melanoma risk[3].
{?|SPF 30 blocks about 97 percent of UVB rays, SPF 50 blocks about 98 percent - the difference is small, but reapplication every 2 hours matters more than higher SPF}
Tanning Myths
Myth: A base tan protects you from sunburn
Reality: A tan provides only SPF 2-4 protection at most and still represents UV damage. There is no safe way to tan from UV exposure.
Reality: A tan provides only SPF 2-4 protection at most and still represents UV damage. There is no safe way to tan from UV exposure.
Myth: Tanning beds are safer than sunlight
Reality: Tanning beds primarily emit UVA rays which penetrate deeper into skin and are linked to melanoma. Studies suggest indoor tanning before age 35 may significantly increase melanoma risk.
Reality: Tanning beds primarily emit UVA rays which penetrate deeper into skin and are linked to melanoma. Studies suggest indoor tanning before age 35 may significantly increase melanoma risk.
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References
- Holick MF, Chen TC (2008). Vitamin D deficiency: a worldwide problem with health consequences. American Journal of Clinical Nutrition. [DOI]
- Passeron T, Bouillon R, Callender V et al. (2019). Sunscreen photoprotection and vitamin D status. British Journal of Dermatology. [DOI]
- Green AC, Williams GM, Logan V, Strutton GM (2011). Reduced melanoma after regular sunscreen use: randomized trial follow-up. Journal of Clinical Oncology. [DOI]