Sunlight and Longevity
Welcome to a very brief update on a very important topic.
If any of you haven’t read my previous article on sunlight, I would urge you to take a look at:
I wanted to make sure you are aware of an important new study that was just released. An article was just published in the peer reviewed “Journal of Internal Medicine”, which may be viewed at the Wiley Online Library at:
The authors of this study reviewed records from nearly 30,000 Swedish women over a 20-year period. They found that women who did their best to avoid sunlight had life expectancies equivalent to women who smoked one pack of cigarettes a day.
Women who got minimal sunlight lived longer, those who received moderate exposure lived even longer, but those who received maximum amounts of sunlight lived the longest!
Additionally, women who had high sun exposure and cancer (including skin cancer and melanoma) lived longer than women who had the same cancers but didn’t recieve sun exposure.
The authors looked at “all-cause” mortality and concluded that extreme sunlight exposure may be related to a small increase in some skin cancers (related to sunburns), they found that sunlight exposure directly correlated with longevity in all groups of women. Most importantly: longevity is clearly and dramatically reduced in those women who work to avoid the sun.
Looking closely at the graphical data published in this article it is also apparent that deaths from all causes (heart disease, cancer and “other”) is lowered across-the-board in the groups with the greatest amounts of sunlight exposure.
Further the authors concluded that:
“Whether the positive effect of sun exposure demonstrated in this observational study is mediated by vitamin D… Vitamin D levels might be just a marker of [adequate] sun exposure.”
This is the first study, that I am aware of, suggesting that Vitamin D may only be a “side effect” of adequate sunlight exposure. This would certainly explain why sunlight exposure, but not Vitamin D levels, are directly correlated with longevity. This also explains why taking Vitamin D supplements does not prolong life or prevent disease, but getting adequate sunlight does.
The benefits from sunlight are tremendous, and for all intents and purposes, they appear to be directly related to sunlight and UV exposure and NOT to the intake of Vitamin D. Vitamin D is probably just one of the many benefits generated in our bodies when we receive adequate sunlight exposure. The sun plays a direct role in hundreds of metabolic pathways that stimulate proper growth and development, prevent depression, and improve immune system functioning. Sunlight keeps the skin healthy, fights acne and makes us stronger.
Excessive sunlight may contribute to wrinkling, but wrinkles are beautiful and show how wise we are!
Even the World Health Organization (WHO) has suggested that healthy sun exposure is about 20 minutes daily, at mid-day, on the equator, and over the entire body surface without clothes! Twenty minutes seems to be a magical number, and the benefits are less profound with greater time.
A reminder: the use of many sunblocks have been associated with higher rates of skin cancer (particularly malignant melanoma). Interestingly malignant melanomas frequently appear on areas of the body that are not exposed to direct sun. Sunblocks are probablematic because these substances prevent the body from generating a tan (the body’s own natural defense against too much sun) and thus they leave the skin more susceptible to radiation damage. Not to mention the fact that many of the ingredients in sunblock are carcinogenic and tend to be absorbed directly through the skin.
Sunburns are never advisable, but daily sun exposure (20 minutes over as much body surface as possible, at mid-day) is extremely important and highly recommended. Don’t fall prey to fear-mongering advertisers trying to sell you sun-block, Vitamin D and calcium pills while frightening you and covering up the real benefits of natural sunlight. Get outside every day and let your skin do what it was designed to do: collect, process and utilize sunlight in a natural photosynthetic, life-generating process.
 Environmental Health Perspectives. 2008 April; 116(4):A160-A167.