Wednesday, January 7, 2009

Sarah Palin, vitamin D and tanning beds, part 4: The truth about tanning beds and melanoma

We have discussed in this “Sarah Palin” series, the fact that she was probably correct in installing (with her own money) a tanning bed in the Alaska Governor’s mansion. We showed that melanoma risk has increased exponentially as sunlight exposure had decreased. We also showed that melanomas occur most frequently on areas of the body that receive the least sunlight. As Dr Frank Garland stated in a conference of vitamin D Scientists in San Diego, California, “Melanoma is a disease of indoor office workers.”[1] He and his brother, Cedric had done research showing that indoor workers had about a 50% greater risk of melanoma than outdoor workers.[2]

In this blog I make the point that not all of the research on tanning beds is bad, although you’d never know it by the broadsides coming out of the American Academy of Dermatology, the American Cancer Society and others who have a very strong financial interest in hiding or refuting any positive news about either sunlight or tanning beds. This and the next article in the series will discuss some of the positive research that has appeared in medical and scientific journals and been ignored.

Several studies have investigated the relationship of tanning-bed use to melanoma and a review of 22 investigations done from 1979 through 2002 showed that only four indicated tanning beds increased melanoma risk; eighteen showed no association.[3] One that showed an increased melanoma risk was conducted by Dr. Philippe Autier and colleagues in Belgium in 1991.[4] However, in 2002 Dr. Autier conducted another study in which no association between tanning bed use and melanoma was found.[5] This report stated, “No result suggested a dose-response curve, and no association was even present for subjects who reported more than 35 hours of cumulated tanning bed use at least 19 yrs before the interview. Our study doesn’t support the possibility that tanning bed use could increase melanoma risk.” Isn’t it interesting that such reports usually die in obscurity?

I looked for other studies that might have come to contrary conclusions and found one from 2007.[6] It was a meta-analysis of 19 studies that concluded tanning beds do increase the melanoma risk. However, when Dr. William Grant assessed the meta-analysis, he noted that the studies failed to take skin type into consideration.[7] He re-analyzed the data and determined: “These results indicate that when studies largely influenced by inclusion of people with skin phenotype 1 [light-skinned non-tanners] without adjustment for skin phenotype are removed from the meta-analysis, no significant relation is found between tanning bed use and risk of CMM [cutaneous malignant melanoma].” There is no doubt that non-tanners, especially if they have large numbers of moles, need to be extremely cautious when they are exposed to ultraviolet (UV) light, whether from sunlight or tanning beds, the reason being that they burn so easily. More than a few seconds of exposure can burn this skin type. However, it appears that all other types can benefit from moderate UV exposure.

Stay tune for more on tanning beds and melanoma in the next chapter regarding Sarah’s tanning bed.

[1] Garland F. Address to the Grassroots health Vitamin D conference, December 2, 2008.
[2] Garland F. et al. Occupational sunlight exposure and melanoma in the USA Navy. Arch Environ Health 1990; 45:261-67.
[3] International Smart Tan Network 2006. Research shows no connection between tanning and melanoma: Why this is misunderstood.
[4] Autier, P. et al. Cutaneous malignant melanoma and exposure to sunlamps and tanning beds: a descriptive study in Belgium.
[5] Autier, P. et al. tanning bed use and risk of melanoma: results from a large multicentric European study. Poster at the XVIII International Pigment Cell conference held 9-13 September 2002 at Egmond, The Netherlands.
[6] International Agency for Research on Cancer Working Group on artificial ultraviolet light (UV) and skin cancer. The association of use of tanning beds with cutaneous malignant melanoma and other skin cancer: a systematic review. Int J Cancer 2007;120:1116-22.
[7] Grant, W. Insufficient evidence exists to link tanning bed use to risk of melanoma for other than those with skin phenotype 1. Sunlight, Nutrition and Health Research Center (SUNARC). March 9, 2007. www.

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Michael said...
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