Indoor tanning—magnitude of the health issue

Journal of Drugs in Dermatology, Feb, 2006

Commercial indoor tanning is unfortunately one of the fastest growing industries in the United States, with sales surpassing $5-7 billion. (1) Reports indicate that between 1986 and 1996 there was a three-fold increase in the percentage of Americans using tanning beds. (2)

This rising trend has serious implications in view of today's skin cancer epidemic. More than a million new cases of skin cancer are diagnosed annually, and the incidence of melanoma, the most serious, and life-threatening form of the disease, is skyrocketing. Moreover, the cancer burden is predicted to double in the next 50 years, as the population ages. The growing popularity of indoor tanning will increase these statistics.

What shall we do to prevent this catastrophe? The significant health risk that indoor tanning poses requires us to lobby for legislation limiting access to tanning parlors, particularly for minors.

Dangerous Tanning Bed Rays

The ultraviolet (UV) radiation of the electromagnetic spectrum is divided into UVC--200-290 nanometers, nm (1 nm = 1 billionth of a meter), UVB--290-320 nm, and UVA 320-400 nm. The majority of UVC and much UVB are absorbed by the earth's stratosphere. Of the radiation reaching the earth's surface, some is UVB, but more than 95% is UVA. Although UVB is known to be 1,000 times more erythemogenic (has the ability to cause redness), UVA penetrates deeply into the skin and mounting research indicates that, like UVB, it is a carcinogen. (3)

It has been shown that tanning bed lamps emit mainly UVA but also a small amount of UVB. Recently marketed lamps can emit either a greater proportion of UVB or higher UVA doses (high-pressure UVA lamps). These lamps emit UVA doses far higher than any previously known. According to Food and Drug Administration (FDA) estimates, they are 10 times greater than the sun. (3) Thus, significant UVA and UVB exposure can result from indoor tanning.

The Many Health Risks

Multiple health risks are related to indoor tanning. Those include severe skin or corneal burns, cataract formation, skin infections, photoaging, exacerbation of photosensitive disorders, and skin cancer. Melanomas and nonmelanomas (basal cell carcinomas, BCCs and squamous cell carcinomas, SCCs) are the most serious of these after-effects. They may develop, because indoor tanning is similar to sunlight in causing DNA alterations in the skin, thus increasing the potential for skin cancer development. (4) Positive associations between indoor tanning and melanoma have been observed. Regular use by women, regardless of age, was associated with a statistically-significant increase in risk of melanoma (after adjustment for sun sensitivity). (5) Another study indicated a greater risk of melanoma with sun-bed use, for young subjects (<45 years of age) with fair skin. (6) An association between indoor tanning and the nonmelanomas has also been previously shown. (3) In light of these studies, our growing understanding of UV exposure and the attendant risk of skin cancer makes it clear that indoor tanning undoubtedly poses the greatest risk for the young.

Vitamin D and UV Rays

The indoor tanning industry evokes fear of a vitamin D deficiency in people lacking exposure to sunlight or indoor lamps. Contrary to recently published reports in the media, vitamin D deficiency and rickets are not as common as portrayed. Australian studies have shown that regular sun protection with a sunscreen, SPF 17, did not result in vitamin deficiency. Nor did this occur in patients with xeroderma pigmentosum who lack the ability to repair DNA and so avoid being out in the sun. What is more, very brief exposure to sunlight is all that is needed to produce sufficient levels of vitamin D, and indoor tanning is clearly not necessary.

Salon Visitors

The indoor tanning industry reports that approximately 28 million Americans use indoor tanning equipment each year, with about one million visits each day. Indoor tanning is common among teenagers; 36.8% of white female adolescents--often those with fair skin who are at the greatest risk for skin cancer--and 11.2% of white males visit the parlors at least once in their lives. (7) In one community, the lifetime prevalence of tanning bed use among female teenagers was 51%. (3) Adolescents who use tanning beds (most often female) are likely to believe that tans are attractive, and so are less likely to use sun protection or to be knowledgeable about skin cancer risks. Those who patronize indoor tanning parlors also tend to be sunbathers, giving them a cumulative risk of skin cancer. Indoor tanning is also highest among youths whose caregivers used indoor tanning lamps in the preceding year.

Consumers' Motivations

A tanned appearance is a strong motivator, as is the desire for relaxation. The pleasure of relaxing on a tanning bed was one of the most common reasons given in a survey among college students. (8) An understanding of motivating factors is relevant, particularly if we are going to suggest alternatives, eg, self-tanning lotions for a tanned appearance, and whirlpool baths or massage for relaxation.