More on preventing skin cancer: Sun avoidance will increase incidence of cancers overall

doi:10.1136/bmj.327.7425.1228-a

BMJ 2003;327:1228 (22 November), doi:10.1136/bmj.327.7425.1228-a

Letter

Sun avoidance will increase incidence of cancers overall

The first 150 words of the full text of this article appear below.

EDITOR—Fry and Verne in their editorial concluded thatsunscreens may create a false sense of security and encourageover-exposure to the sun.^1
2 Sunscreens should not be reliedon to prevent melanoma. Typical sunscreens only weakly absorbultraviolet A light, which is 97% of ultraviolet radiation andis nearly as carcinogenic as ultraviolet B light. The typicalprotection factor for ultraviolet A is 2-4 for chemical sunscreens.³Absorption of ultraviolet A is not included in calculation ofthe sun protection factor.

The authors' advice to avoid the sun would not be the best strategyfor reducing overall incidence of cancer. Recommending moderateexposure to the sun would be more prudent.

Solar exposure is the main source of vitamin D. Vitamin D andits metabolites reduce the risk of cancers of the colon,^4
5 ^w1w2 breast,^w3-w5 and prostate,^w6-w8 and other cancers.^w9 Sincethe United Kingdom is located at northern latitudes supplementationof . . . [Full text of this article]