What are the effects of tanning beds and natural sunlight on the skin. What factors contribute to the development of skin cancer? How can we protect ourselves from UV lights' harmful rays? How does "sunblock" work and does it pose any risks?

Exposure to sunlight is important in the synthesis of vitamin D. However, UV overdose has damaging effects on human skin, whether the source of UV is the sunlight or tanning beds. Ultraviolet rays speed up the skin’s aging process, affect the immune system, contribute to the development of infectious disease, and can lead to skin cancer, including melanoma (Gibson, 2010, para.1). Excessive UV radiation results in sunburn; damage to the epidermis can occur in two hours of sun exposure, resulting in erythema (eMedicine, 2010, para. 3). 


The most common type of cancer in the United States, the skin cancer, has as the most frequent cause the UV rays exposure, but also high X-rays levels exposure, contact with specific chemicals such as arsenic or hydrocarbons, or immunosuppression-impairment of the immune system. Heredity and environment also play a major role. The risk of skin cancer increases for people with fair skin (eMedicine, 2010). 

The best way to protect the body from UV rays is to stay out of the sun, especially during hot, summer days: reduce sun exposure, stay in shade as much as possible, cover the body, avoid tanning beds, check the skin regularly for moles, and use sunscreen with a high sun protection factor.

Sunscreen blocks the sun’s harmful UV rays, and it is therefore essential in reinforcing the skin’s protection. Recent studies indicate sunscreens with 1 to 6 percent oxybenzone do not presents any risks of skin irritation. The mineral-based sunscreens with ingredients of zinc oxide and titanium dioxide seem to also be safe and effective (Mayo Clinic, 2010, para 12-13). However, a Food and Drug Administration (FDA) report from 2007 shows there is no proof sunblock prevents skin cancer, recommending appropriate clothing as the best solution of avoiding UV rays exposure. The same FDA report suggest there is however sufficient evidence that sunblock might increase the risks of melanoma (Breyer, 2010, para. 5-6).


Sources:

Ambrose Video (2005). Body Atlas: Skin.

Breyer, M. (2010). Risks of sunscreen. Electronically retrieved from http://www.care2.com/greenliving/the-dangers-of-sunscreen-new-report.html#

eMedicine (2010). Skin cancer causes. Electronically retrieved from http://www.emedicinehealth.com/skin_cancer/page2_em.htm#Skin Cancer Causes

eMedicine (2010). Sunburn. Electronically retrieved from http://emedicine.medscape.com/article/773203-overview

Gibson, L. E. (2010). Are tanning beds safer than natural sunlight? Electronically retrieved from http://anna-hall.com/are-tanning-beds-safer-than-natural-sunlight-1-of-3/

Mayo Clinic Staff (2010). Best sunscreen: Understand sunscreen options. Electronically retrieved from http://www.mayoclinic.com/health/best-sunscreen/MY01350