Sunlight, Vitamin D, Sunblock, and Cancer

For years, medicine had little awareness of the dangers of sun exposure. Once it was discovered that suntanning and sunburn were major factors in instances of skin cancer, we began hearing about it. We’ve heard for so long that it is unhealthy to spend time in the sun that we are now seeing a prevalence of vitamin D deficiency around the world. Today, most people do not get sufficient sun exposure to support the natural production of vitamin D in the body. On the other hand, sun exposure increases the risk of skin cancer. Is it possible to find a middle ground? And does it even matter?

It Matters

It does matter that we look at the connections between sunlight, vitamin D, sunblock, and cancer. Vitamin D is involved in several physiological processes, including:

  • The regulation of calcium and phosphate in the bloodstream
  • The facilitation of optimal bone growth and mineralization
  • Immune support that helps T-cells defend against infectious bacteria and viruses
  • The modulation of gene expression related to cell proliferation, differentiation, and apoptosis (vitamin D deficiency has been linked to various types of cancer)
  • The reduction of systemic inflammation

Vitamin D and Sunlight

Studies suggest that sunlight is the best way to promote adequate vitamin D levels. When the skin absorbs sunlight, the body makes vitamin D out of cholesterol. The good news it does not take much for this to occur. People with lighter skin need as little as 20 minutes of sunlight (without sunglasses or sunscreen) to stimulate vitamin D production. People with very dark skin may need as much as 2 hours of exposure to get the same effect.

Sunlight and Skin Cancer

If we spend more time in the sun than our melanin level can tolerate (melanin is the substance that colors the skin), we begin to turn red. Redness eventually turns to a bronzed tan. Redness also indicates cellular damage and the increased risk of both premature aging and skin cancer. If you are interested in maintaining healthy vitamin D levels, spend only a short time in the sun, preferably during the early morning hours. If your skin begins to turn red, you’ve gotten too much.

Skin Cancer and Sunblock

Most people are aware that they need to wear sunscreen daily. This can be applied after a morning sunlight session to promote vitamin D production. For anti-aging benefits, broad-spectrum sunscreen should be applied to relevant areas such as the face, neck, and chest. The arms and hands are also vulnerable areas, even during the winter months.  For anti-cancer benefits, broad-spectrum sunscreen should be worn on all exposed skin, including the legs, feet, and toes, anytime more than 20 minutes will be spent in the sun.

The American Society for Mohs Surgery proudly supports dermatologists advancing their surgical skills. We also support patients by providing a directly of Mohs surgeons across the country. For more information on our courses or a dermatologist in your area, call (800) 616-2767.

Posted in: Skin Cancer, Skin Care

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