Solar Energy 
Avoid too much of a good thing 

STANLEY R. MOHLER, MD
Sport Aviation - August 2000

Solar energy, the sunshine that makes summer enjoyable and draws people to outdoor activities like AirVenture. But too much of a good thing can lead to bad things people don’t enjoy, things like sunburn and skin cancer. Prevention is the only way to avoid the pain and suffering too much sunshine can cause. Light-complexioned people are prone to sunburn and should wear hats, long-sleeved shirts, and trousers from mid-morning to late afternoon. This seems to be simple common sense, but some have learned this admonishment the hard way and have spent many hours with dermatological plastic surgeons having skin cancers removed. Failure to remove these cancers and/pre-cancers can lead to an even harder lesson, large expanding ulcerations that, if on the nose, eyelids, or ears, can cause irreversible, incredibly serious consequences (loss of these parts!). 

Preventing skin cancer is easier and less expensive. In addition to the hat, long-sleeved shirt, and trousers, people should use sunscreen on their exposed skin. A sun protection factor (SPF) of 15 or higher is generally recommended. What sunscreen protects us from is ultraviolet light, which is arbitrarily divided into UVA, the longer wave length portion of the UV spectrum, and UVB, the shorter UV wave lengths. UVA can penetrate several millimeters into the skin and trigger “melanocytes,” which generate additional dark pigment particles that gradually migrate to the skin’s surface as normal skin grows and sheds.

For those who tan readily, this skin-darkening process is fairly efficient, and the result is a nice self-protecting suntan. Suntan parlors use artificial UVA sunlight to bring about a tan. But people should think seriously about getting a tan in this manner because in fair-skinned individuals, the development of skin cancer is related to repeated exposures to ultraviolet light. “Basal” cell carcinoma is the most common type of skin cancer in the United States. It’s rarely fatal because surgical removal is available throughout the country, but severe disfigurement, especially on the face, can result if people don’t deal with it in its early stages. 

“Squamous” cell is a second type of skin cancer. People must deal with it in its relatively early stages because it is aggressive and can metastasize—get into the blood and spread to various parts of the body. 

The third type of skin cancer—the melanin-containing melanocarcinoma—is extremely dangerous. It develops from the dark pigment cells in the skin, which are especially susceptible to genetic damage from UV light and to the subsequent conversion into cancer cells. These cancer cells have the ability to stimulate the growth of capillaries. When these cancer cells break off and travel to other parts of the body, they begin stimulating capillary growth, and this results in a supply of nutritious elements that are necessary for subsequent multiplication and growth. Squamous cell carcinoma also has the ability to stimulate capillary growth, but it doesn’t stimulate the growth with the extreme efficiency that melanocytic cancers do. (Basal cell carcinoma does not have the ability to stimulate capillary growth.) 

In the past 30 years, the increase in melanocyte cancers has accelerated, a circumstance attributed to significantly more UV exposure in outdoor activities. Beaches reflect sunlight so that more is received over the body. The same occurs on airport ramps. Early detection is key. A developing basal cell carcinoma is first visible as a slightly raised site on the skin that has a few visible capillaries on the surface. Over weeks or months, it tends to ulcerate, and it’s best to have it surgically removed before it reaches this stage. An early sign of squamous cell carcinoma is a growing, spreading reddish lesion on the skin, and it, too, should be expeditiously removed. A black, slightly raised mole should be removed as a preventive measure. If the edges begin to change, people should consult a physician with all reasonable haste. This may be a developing melanoma cancer that, as stated above, is the most aggressive form of skin cancer. Fear of sunshine should make people afraid to go outside. 

Some sunlight is necessary, and therefore healthy, for the skin to generate vitamin D from the ingested precursor. Two 15-minute exposures of the face and hands to outdoor sunlight three times a week should result in sufficient vitamin D to meet your body’s needs. Vitamin D is a “fat-soluble” vitamin, which means it’s stored in the fat cells. 

Accordingly, most people who are in and out for short periods during the day will build a nice reserve of vitamin D, enough for a few weeks of indoor seclusion. Vitamin D can be taken by mouth in over-the-counter preparations, but with a balanced diet and some reasonable sun exposure there should be normally no deficiencies developing vitamin D. (Caution: Taking an excessive amount of over-the-counter vitamin D can damage the bones and other organs.) 

As a small boy growing up in Texas, I was encouraged to spend a great deal of time enjoying the bountiful sunlight, with or without protection from excess exposure. The concept was that sick individuals were pale in color and healthy persons were not. My friends and I made sure we came out on the healthy side of the equation. 

Unfortunately, many of us are now dealing with crops of skin cancers that had their origins decades ago. Some of us are no longer here, victims of melanosarcoma. It bears reemphasizing that the intelligent approach is the use of reasonable protection from excess solar energy. I have seen sunburned individuals on the flight line who very likely will be paying later. A broad-rimmed hat, some sunscreen, and a long-sleeved shirt and slacks are sufficient for susceptible persons who want to avoid later skin surgeries. Protection of infants and small children is a major consideration. Parents! Don’t forget to protect your children from the sun. 

Enjoy AirVenture 2000 and other flight gatherings, and routinely incorporate healthy practices that will assure continuing health long into the future. Now, let’s go out into the sun—with the proper preparations.