Sunlight, and plenty of it, may be the best method for reducing the risk of melanoma. An impressive piece of research on melanoma and sunlight appeared recently in the European Journal of Cancer. Dr. Julia Newton Bishop and colleagues (thirteen scientists in all) researched sunlight exposure habits and compared those habits to the risk of melanoma in an English population. Among other notable findings was a considerable reduction in melanoma risk among those who received the highest summer sunlight exposure on weekends. Compared to those with the least exposure to sunlight on weekends, those who received 4-5 hours of sunlight during the weekends had a reduced risk of melanoma of 28%, and those who received more than 5 hours had a reduced risk of melanoma of 33%.
In general, the English have very light complexions—complexions that are known to be more susceptible to melanoma, a fact that makes the research even more interesting. One can only conclude from this information that regular sunlight exposure protects against melanoma. In reality, this result should come as no surprise; at least 16 studies have shown indoor workers are much more likely to contract melanoma than outdoor workers. Other research points out that melanomas occur much more frequently on areas of the body that receive little or no exposure to sunlight.
Finally, it is quite obvious that outdoor living has decreased dramatically since 1935. Based on materials furnished by the Department of Labor Statistics, I calculated that sunlight exposure has decreased by at least 83%.. Yet, the Melanoma International Foundation has stated, “Melanoma is epidemic: rising faster than any other cancer and projected to affect one person in 50 by 2010, currently it affects 1 in 75 . In 1935, only one in 1500 was struck by the disease.” In other words, as sunlight exposure has dropped profoundly, melanoma risk has increased by 3,000%! Based on those facts, the idea—that sunlight exposure is the cause of melanoma—is counterintuitive at best, and ludicrous at worst.
It is likely that vitamin D production in the skin, in response to sunlight, is a major player in reducing the risk of melanoma. Enzymes in melanoma cells form active vitamin D, which in turn can lead to melanoma cell death, and in lab experiments, active vitamin D can destroy melanoma cells. In fact, vitamin D works in many ways to reduce cancer. Here are just a few:
1. Vitamin D promotes apoptosis (normal cell death) so that cancer cells die normally.
2. Vitamin D inhibits proliferation (out-of-control growth) of cancer cells.
3. Vitamin D inhibits angiogenesis in cancerous tissue. Angiogenesis is the formation of blood vessels. It is a process that provides blood and nutrients to newly formed tissue. If angiogenesis in cancer cells can be stopped, the cells die. Vitamin D acts a selective angiogenesis inhibitor—it retards the growth of new, undesirable “feeder” blood vessels into cancer cells.
4. Vitamin D inhibits metastasis (the spreading of cancer cells from the initial location of the disease to another location).
The key to safe sunlight exposure is to avoid burning and to gradually develop a tan. Caution is always in order. To prevent melanoma, we need not to avoid the sunlight but safely embrace it!
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