GreenMedInfo is an excellent database for people interested in learning about natural medicines. Their article below about a meta-analysis of dozens of studies measuring the cancer protective benefits of sunlight exposure and the subsequent amounts of vitamin D that it generates, is important reading.
Of course, some of you may be worried about the cancer causing effects of sunlight exposure, but it takes only 10 minutes or less of sunlight to generate significant amounts of vitamin D and getting exposure once a week, is all that is necessary.
“Indeed, a groundbreaking new meta-analysis on the sunlight-vitamin D connection published in the journal Anticancer Research and based on data from over 100 countries, found “strong inverse correlations with solar UVB for 15 types of cancer,” with weaker, though still significant evidence.
The relevant cancers were: bladder, breast, cervical, colon, endometrial, esophageal, gastric, lung, ovarian, pancreatic, rectal, renal, and vulvar cancer; and Hodgkin’s and non-Hodgkin’s lymphoma. Weaker evidence exists for nine other types of cancer: brain, gallbladder, laryngeal, oral/pharyngeal, prostate and thyroid cancer; leukemia; melanoma; and multiple myeloma.
Sunlight exposure, after all, is essential for health from the moment we are born. Without it, for instance, infants are prone to developing neonatal jaundice. The very variation in human skin color from African, melanin-saturated dark skin, to the relatively melanin de-pigmented, Caucasian lighter-skin, is a byproduct of the offspring of our last common ancestor from Africa (as determined by mitochondrial DNA) migrating towards sunlight-impoverished higher latitudes, which began approximately 60,000 years ago.
In order to compensate for the lower availability of sunlight, the body rapidly adjusted, essentially requiring the removal of the natural “sunscreen” melanin from the skin, which interferes with vitamin D production. While a life-saving adaptation, the loss of melanin likely has adverse health effects, which include losing the ability to convert sunlight into metabolic energy, increased prevalence of Parkinson’s Disease (which involves de-melanization of the substantia nigra), and other effects, which we will discuss in detail in a future article. For now, it is important to point out that within the span of only 60,000 years (a nanosecond in biological time), many of the skin “color” differences among the world’s human inhabitants reflect how heavily genetically-conserved was the ability of the human body to produce vitamin D.
It should also be pointed out that vitamin D is to sunlight, what ascorbic acid is to the vitamin C activity in food. In other words, sunlight likely provides a greater spectrum of therapeutic activity (when carefully meted out, preferably during solar noon) than supplemental vitamin D3.” (This may or may not be true, but everyone should be supplementing a minimum of 1000 IU/day of vitamin D-3).
Curt Hendrix, M.S., C.C.N., C.N.S