SOURCE: SUNARC

SUNARC - Sunlight Nutrition and Health Research Center

March 15, 2010 11:28 ET

New Study by SUNARC Shows Tanning and Melanoma Link Scientifically Flawed

IARC Sunbed Review Ignored Obvious and Crucial Confounding Factors, Said Grant

SAN FRANCISCO, CA--(Marketwire - March 15, 2010) - A new study published in the peer-reviewed journal "Dermato-Endocrinology" shows that there is no statistically significant connection between sunbeds and melanoma in those who can develop suntans (skin type II-VI), with increased risk centered only on those whose skin is so fair it cannot tan (skin type I).

William B. Grant, PhD, a former NASA atmospheric research scientist and founder of SUNARC, Sunlight, Nutrition and Health Research Center (SUNARC), re-examined the same epidemiological data used by the International Agency for Research on Cancer (IARC) group from their findings in 2007 titled, "The association of use of sunbeds with cutaneous malignant melanoma and other skin cancers: a systematic review." Grant's study strongly challenges this review and argues it is both flawed and cannot be used as the basis for U.S. health policy.

The IARC review originally claimed a 15% increased risk of melanoma for ever use of sunbeds and a 75% increased risk in melanoma for respondents who had ever used or first used a tanning bed prior to age 35. Grant's findings show that with the removal of those with skin type I who possess the greatest genetic risk of cutaneous malignant melanoma (CMM), there fails to be any statistically significant link between ever use of indoor tanning facilities and CMM.

ACCORDING TO GRANT'S ANALYSIS:

--  The reported 75% increased risk of melanoma for those ever having 
    used a sunbed prior to age 35 drops to a 25% reduced risk of melanoma 
    in the United States based on a scientifically-centered reanalysis of 
    the data in the IARC report.

--  When skin type I is omitted from the IARC analysis, the reported 15% 
    increased risk in melanoma fails to remain statistically significant. 
    This is based on a meta-analysis of the 14 studies not from the UK, 
    where skin type I is most prevalent.

--  The IARC study inappropriately combined four studies from northern 
    Europe, one from the UK, one from Canada, and one from the U.S. in the 
    analysis of first use of sunbeds before the age of 35 years. There are 
    vast differences between American and European sunbed regulations and 
    use. US regulations do not allow Skin Type I patrons to tan, European 
    tanning beds are often used at home or are unsupervised and do not 
    follow the regulations in the U.S. The study fails to state that its 
    findings are not, and should not be considered "universal findings."

"The reason this 'Skin Type I' distinction is so important is that we now know that UV avoidance among people who can develop a tan has contributed to epidemic-level vitamin D deficiency in North America, with 3 out of 4 Americans being vitamin D deficient today," said Grant. "Our public health messages about the benefits of UV radiation from any source need to recognize this."

The IARC report was a meta-analysis of epidemiologic surveys -- questionnaire surveys designed to retrospectively identify correlations, but which do not by nature identify causation. As stated in the IARC report, "Epidemiologic studies to date give no consistent evidence that use of indoor tanning facilities in general is associated with the development of melanoma or skin cancer."

Melanoma's connection with UV exposure is controversial, as research clearly shows it is more common in indoor workers than in outdoor workers and is more common on parts of the body that aren't regularly exposed to sunlight, implicating sun burning rather than regular tanning.

THE IARC REVIEW ALSO NEGLECTED TO:

--  Find a dose-response relation between the amount of sunbed use and 
    risk of melanoma -- which would be key to establishing a causal 
    relationship.
--  Recognize a growing body of literature that shows that non-burning 
    UVB exposure reduces the risk of CMM, and that recreational exposure 
    and sun burning increases risk
--  Cite other potential reasons for increases in melanoma, including: 
    geography, differing sunbed regulations in various locations, gender, 
    increased travel to sunny places, greater levels of sunscreen use, or 
    the nature of solar UV exposure.

IMPORTANCE OF SUNLIGHT AND VITAMIN D TO OUR SURVIVAL

Another recent study from Grant, "In Defense of the Sun," published in Dermato-Endrocrinology, suggests that raising vitamin D blood levels to 45 ng/ml could reduce mortality rates in the United States by 15% and prevent up to 400,000 premature deaths from vitamin D deficiency-related diseases annually. Such diseases include many types of cancers, cardiovascular disease, heart failure, respiratory infections, diabetes, and falls and fractures.

Vitamin D researchers today recommend vitamin D blood levels should be maintained above 40-60 ng/ml. At least 2,000 IU of vitamin D daily in addition to dietary sources and casual solar UV irradiance are required to maintain those levels. According to peer-reviewed, published research, indoor tanners have those levels, but non-tanners do not.

Indoor tanners:         42-49 ng/ml
American average:       23-25 ng/ml

In addition, two 2009 Swedish studies of indoor tanners showed a reduced risk of endometrial cancer and thrombotic events. A recent study at Boston University School of Medicine also found that blood levels of D3 were almost twice as high in sunbed users as in non-users. Sunbed users' bone densities at the hip were also significantly higher.

"There is conclusive evidence that indoor tanning in a non-burning fashion offers a tremendous source of vitamin D," Grant says. "The benefit of regular UV exposure as the body's only true natural source of sufficient vitamin D production easily outweighs the manageable risks associated with overexposure to sunlight," Grant says. "We know now through more than 2,000 papers published in 2009 that smart UV exposure and increased vitamin D levels will not only save lives, but also extend and increase our quality of life."

About Dr. William Grant:

Dr. William Grant is a former NASA PhD and founder and current Director of SUNARC (Sunlight, Nutrition and Health Research Center). SUNARC, www.sunarc.org, is devoted to research, education, and advocacy relating to the prevention of chronic disease through changes in diet and lifestyle. Grant was formerly a senior research scientist in the fields of optical and laser remote sensing of the atmosphere and atmospheric sciences at SRI international, the Jet Propulsion Laboratory and the NASA Langley Research Center. Grant is author and coauthor of over 70 articles on ultraviolet irradiance and vitamin D and 100 articles on other topics in peer-reviewed journals and has contributed half a dozen chapters to additional books. He was elected fellow of the Optical Society of America in 1992. Dr. Grant is known for publishing the first paper linking diet to Alzheimer's disease, presenting strong evidence that sweeteners are an important risk factor for coronary heart disease for women, and identifying the risk of vitamin D deficiency for ten internal cancers among other ground-breaking research. Grant graduated with a Ph.D. in Physics from U.C. Berkeley.

Contact Information