One thing most Americans seem to believe is that sunlight must be avoided for it causes skin cancer, especially malignant melanoma. We decided to give a little quiz about the subject.

1. What is the vitamin most people in the United States are deficient in?

1. Vitamin C
2. Vitamin K
3. Vitamin D
4. Vitamin E

The answer is 3, vitamin D.

2. Imagine that Dr. von Eschenbach, M.D., the director of the National Cancer Institute (NCI), visited his dermatologist who examined him and diagnosed a small squamous cell cancer on his nose. His dermatologist, who noted that Dr. von Eschenbach had the quaint custom of regularly exposing his body to short courses of noonday sunlight on the roof of the National Library of Medicine, advised Dr. von Eschenbach to now totally avoid the sun.

As Dr. von Eschenbach has read every scientific article ever written on cancer, his reaction was:

• He thanked his dermatologist but knowing the prognosis is grim for those who develop squamous cell skin cancers, went home and wrote a will.

• He immediately arranged to have a complete examination by an internist as Dr. von Eschenbach knows his chances of developing internal squamous cell cancers is much higher after being diagnosed with a squamous cell skin cancer.

• He knew he must now avoid the sun entirely, so he bought cases of sunblock and lots of clothes that would totally protect his skin. He vowed to never let another ultraviolet ray of sunlight ever strike his unprotected skin.

• He jumped up, smiled broadly, hugged his dermatologist, arranged to have the skin cancer removed, put some unblock on his face and hands, took of his shirt and changed into shorts for the walk to his car and then drove home to tell his loved ones the good news.

The correct answer is D. Dr. von Eschenbach knows that virtually all squamous cell skin cancers are easily treated when caught early and that fewer than 600 Americans die every year from squamous cell skin cancers compared to tens of thousands who may be dying from internal malignancies induced by vitamin D deficiency.

Furthermore, he knows the strong inverse relationship between squamous cell skin cancers and the subsequent development of internal cancers has been known more than 60 years. He also knows that inverse relationship led to one of the first modern theories of cancer (that squamous cell skin cancers conferred immunity against various visceral cancers), which is better explained by sun exposure increasing both squamous cell skin cancers and calcidiol levels.

Furthermore, he knows that the inverse association between sun exposure and several common internal malignancies is robust and has been documented repeatedly. Furthermore, he knows that one of the best things he can do to reduce his chance of getting up to 13 different serious internal cancers is to continue to maintain his healthful levels of serum calcidiol [25(OH) D] by consistent safe sun exposure. If he preferred to totally avoid the sun and oily fish, relying on vitamin D supplements instead, he would need to take between 3,000 to 5,000 IU of cholecalciferol a day to maintain a 25 (OH)D level above 40 ng/ml.

References:

• Apperly FL. The relation of solar radiation to cancer mortality in North America. Cancer Res 1941; 1:191-5
• Prevention Medicine November, 1990;19(6):614-22.
• Cancer Causes Control January, 1992;3(1):95-9
• International Journal of Epidemiology December, 1994;23(6):1133-6
• Cancer December 15, 1992;70(12):2861-9
• Cancer Epidemiol Biomarkers & Prevention May, 1999;8(5):399-406
• Lancet November 18, 1989;2(8673):1176-8

3. The latest evidence suggests 21,000 Americans die every year from internal malignancies associated with inadequate UVB exposure?

A. True
B. False

True. Actually Grant feels the number is an underestimate and is coming out with an even more frightening estimate.

References:

• Cancer March 15, 2002;94(6):1867-75

4. As malignant melanoma is caused by chronic sun exposure, the incidence of malignant melanoma is more common on the hands, is more common in those who work outdoors and is less common in those who use sunscreen.

A. True
B. False

False. Although malignant melanoma does increase with age, the increase is not dramatic as it is with the skin cancer most clearly associated with chronic sun-exposure, squamous cell skin cancer. And, unlike squamous cell carcinoma, malignant melanoma is most common on relatively less exposed areas (backs in men and upper legs in women), is less common in outdoor workers than indoor ones and evidence to date does not show regular sunscreen use reduces its incidence.

Instead of being caused by chronic sun-exposure, malignant melanoma is a multifactorial disease, the sun-exposure component of which appears to be best explained by repeated intermittent intense exposure (sunburn) in a population that usually avoids the sun (vitamin D-deficient population).

References:

• International Journal of Cancer October 29, 1998;78(3):276-80
• International Journal of Cancer March 1, 2000;85(5):627-32
• British Journal of Cancer September, 1988;58(3):385-91
• International Journal of Cancer April 15, 1985;35(4):427-33

5. For many years, the regular use of sunblock may have actually increased the incidence of melanoma.

A. True
B. False

True. Until a few years ago, sunblock usually blocked the burning (and vitamin D producing) UVB while allowing the more deeply penetrating, UVA. Thus, they may have contributed to the rising incidence of malignant melanoma by allowing users to stay in the sun for hours without burning, while their skin soaked up the highly penetrating UVA radiation.

The best sunlight recommendations to prevent malignant melanoma may turn out to be to regularly expose your entire unsunblocked skin to very short periods (one-third the time it takes for your skin to begin to redden) of direct noonday sunlight during the correct season of the year being careful to never let your skin get red or burn.

References:

• Annnals of Internal Medicine December 16, 2003;139(12):966-78
• International Journal of Cancer Octoboer 9, 1997;73(2):198-203.

6. Pretend that Kenneth, director of the National Institute of Environmental Health Sciences, was asked if the American Academy of Dermatology (AAD) recommendations to totally avoid sunlight might have helped cause the rising incidence of melanoma and other diseases over the last 20 years by contributing to the current pandemic of vitamin D deficiency. What should his answer be?

A. Yes
B. No

Yes. The American Academy of Dermatology press releases and spokesmen are particularly misinformed about vitamin D and appear to be giving information that increase the risks of developing a multitude of vitamin D deficiency-related illness (including hypertension, heart disease, cancer, autoimmune disease, diabetes, depression, and, perhaps, even malignant melanoma).

Raymond L. Cornelison Jr., MD, president of the American Academy of Dermatology said, " People who practice proper sun protection and are concerned that they are not getting enough vitamin D should either take a multivitamin or drink a few glasses of vitamin D-fortified milk every day. The dangers of exposing oneself to carcinogenic UV light from the sun, even for a few minutes, are firmly established, particularly since dietary intake of vitamin D can completely and easily fulfill our needs."

Dr. Cornelison and the AAD are putting their member dermatologists at risk for future malpractice liability with such incompetent advice. When dermatologists assume control of the vitamin D system by recommending their patients terminate sun exposure, they are required to ensure their patients have an adequate vitamin D status and that can only be assured by 25(OH) D (calcidiol) levels. Dr. Cornelison seems to be unaware that diet, without sunlight, can rarely supply adequate vitamin D and that one multivitamin (400 IU of vitamin D) a day, without sunlight, will actually ensure vitamin D deficiency.

Just like an anesthesiologist, who assumes responsibility for the airway on the patient she intubates, dermatologists who tell patients to totally avoid the sun assume responsibility for their patients' vitamin D system. A number of academic dermatologists have said just that. See if you can pick out the following quote in the two references listed below: "It would seem mandatory to ensure an adequate vitamin D3 status if sun exposure were seriously curtailed, certainly in relation to carcinoma of breast, prostate and colon and probably also malignant melanoma." Coming from an academic dermatology center, it sounds like the kind of statement that juries take into account when trying to decide the applicable Standards of Care.

References:

• British Journal of Dermatology August, 2002;147(2):197-213
• British Journal of Nutrition May, 2003;89(5):552-72.
• Journal of Cellular Biochemistry February 1, 2003;88(2):296-307

Humans evolved naked in the sun and have lived most of our time on earth within 30 degrees of the equator. Clothes are a recent addition, as are the vitamin D-reducing effects of cities, indoor work, automobiles and sunblock. We will ask one more question.

7. The majority of Americans have 25(OH)D (calcidiol) levels most similar to which of the following groups:

A. Old World, non-human primates living in the wild.
B. New World non-human primates living in the wild.
C. Modern-day agricultural humans living near the equator.
D. Modern-day humans spending some of their time in a natural state (lifeguards).
E. Lab rats.

You guessed it!