Font Size

Sunscreen and Sunblock (cont.)

Sunscreens and Vitamin D Deficiency

Aside from a feeling of well-being and skin darkening, the major benefit of ultraviolet light is to induce the synthesis and storage of vitamin D in the skin. There is no question that if one is darkly pigmented, lives in a northern latitude, and practices sun avoidance it is possible to develop vitamin D deficiency. This can be avoided by taking vitamin supplements containing sufficient amounts of vitamin D. The American Academy of Dermatology recommends taking 1,000 international units daily. In addition, vitamin D-fortified foods like milk are helpful. Although there is accumulating evidence that vitamin D may have important effects on cancer prevention and bone health, the optimum blood level is as yet unknown.

Does Sunscreen Expire?

Many manufactures print an expiration date on the product container. If there is no expiration date, then it is assumed that the product will last three years from the date of purchase.

Medically reviewed by Joseph Palermo, DO; American Osteopathic Board Certified Internal Medicine


Burnett, Mark E., and Steven Q. Wang. "Current Sunscreen Controversies: A Critical Review." Photodermatology, Photoimmunology & Photomedicine 27. Chichester, U.K.: John Wiley & Sons A/S, 2011: 58-67.

Medically Reviewed by a Doctor on 11/17/2017
Medical Author:

Sun Safety Quiz IQ

Must Read Articles Related to Sunscreen and Sunblock

Wrinkles Wrinkles are normally found in healthy skin. learn more >>

Patient Comments & Reviews

The eMedicineHealth doctors ask about Sunscreen and Sunblock:

Sunscreen and Sunblock - Preferred Brand

Tell us the best brand of sunscreen you've bought.

Sunscreen and Sunblock - Ingredients

Are there any ingredients that you avoid when shopping for sunscreen?

Sunscreen and Sunblock - Sun Protection for Babies

What do you do to protect your baby from the sun?

Sunscreen -- User Experience

Tell us the best sunscreen that you've bought.

Medical Dictionary