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Sunlight: its Healing and Harmful Effects*

We all have heard that negative health consequences can result from too much exposure to sunlight. Excessive sunlight damages the skin and increases the probability of skin cancer. Less known by most people, insufficient sunlight results in poor calcium assimilation and failing general health, can cause severe psychological depression, and likely contributes to being overweight. Thus it is wise to get an exposure to the sun but not to the point of damage. An excellent article in Scientific American should be read for information about the harmful and healing effects of the sun.

In recent decades, the medical profession has advised us to use “sunscreen” preparations and to minimize our exposure to sunlight to reduce the probability of acquiring skin cancer. At the same time, the medical profession advised us not to take vitamin and mineral supplements and warned that supplements of Vitamin D were especially dangerous. Ironically, we were told that taking more than 400 units per day of Vitamin D could cause hypervitaminosis even though our bodies produce many times that amount of Vitamin D after a 15-minute exposure to sunlight. In the past decade, the incidence of osteoporosis has increased dramatically. Recent studies suggest that adults need more than 400 units of Vitamin D per day. Other studies indicate a much-higher safe upper limit of adult Vitamin D intake per day.

Sunscreen preparations may be harmful. For example, it is possible that while a sunscreen protects against the rays that cause burning, it may not protect against the rays that cause cancer. The best course is to be mindful of the fact that the skin itself builds up its own natural protection to the harmful effects of the sun through the production of the dark pigment, melanin. The presence of melanin is commonly called a suntan. Each genetic type has a different capacity to produce melanin. Those with blond or red hair or with blue eyes are much more susceptible to the sun than those with dark hair. Of course, dark-skinned people whose ancestors originated in tropical areas of the world have the greatest capacity to withstand the sun.

When exposure to the sun is reduced, the melanin becomes absorbed. This adaptation makes sense because sunlight is necessary, and too much melanin would excessively block needed sunlight. Thus, during winter, when exposure to the sun is greatly reduced, protection diminishes. The problem arises when there is a sudden rather than gradual increase in exposure. Upon the return of warm weather, is common for those who have lost most of their protection to sunlight to suddenly expose themselves to hours of intense sunlight on the first clear, bright day. Thus they receive not only direct sunlight but also the ultraviolet light reflected by the sky. The amount of exposure is then many times that which is optimal, and, of course, much damage then occurs.

It should be understood that the effect on melanin production in response to an increased exposure to the sun takes about two weeks to develop. With this fact in mind, you should become attuned to your degree of vulnerability to the sun, and work up to the point where full exposure is safe. Excessive exposure is evidenced by reddening the next day or by eventual blistering and loss of one or more layers of the skin. Once the skin has been overexposed to sunlight, damage of a serious nature has occurred. At that point get no further exposure until the skin has healed. Then, build up very slowly to give the new skin a chance to become protected.

The use of soap removes natural oils from the skin that protect it from the harmful effects of sunlight. It is also likely that a dietary deficiency of oils rich in essential fatty acids lowers the protective ability of the skin. Flax seeds, pumpkin seeds, walnuts, and sunflower seeds are rich in the essential fatty acids. Eating them produces a healthy, silky, glowing skin.

Excessive exposure to sunlight produces free-radical damage within the living cells below the surface of the skin. This damage is somewhat offset by antioxidants such as vitamin E. Taken orally in 1,000-i.u. amounts a day, vitamin E is said to vastly reduce susceptibility to sunburn. My experience has borne out this protective effect.


*From Robert Chuckrow, The Intelligent Dieter’s Guide, Rising Mist Publications, Briarcliff Manor, NY, 1997.

“Sunburn,” Scientific American 219, 38 (Jul 1968).

Gary Price Todd, M.D., Nutrition, Health, & Disease, Whitford Press, West Chester, PA, 1985, p. 135.


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