By Julia Ai, MD

For those of us in the northern climates, heading into spring and its skin-exposing clothing can be a frightening prospect. To tan or not to tan is the question. And its corollary is: Are tanning beds a safer alternative to sun exposure?

Natural sunlight exposes a person's skin to ultraviolet radiation, including ultraviolet A (UVA) and ultraviolet B (UVB) wavelengths. Similarly, tanning beds generally feature lights that emit UVA (95 percent) and UVB (5 percent) radiation.

Exposure to UVA immediately darkens pigment in the basal layer of the skin, which creates a tan. However, UVA radiation damages the DNA of skin cells and induces DNA mutations. As the skin cells try to repair the DNA damage, particularly as a person ages, this cellular repair mechanism is more prone to error. Because the cell does not find and destroy DNA mutations, the damaged DNA can replicate, leading to skin cancer.

In addition to the increased risk of skin cancer from tanning beds, UVA exposure causes premature aging -- wrinkles, irregular pigment spots and loss of skin elasticity. UVA waves penetrate the skin more deeply than UVB, causing damage on a deeper level. UVA rays destroy collagen and connective tissue beneath the outer layer of the skin.

There is no such thing as a healthy tan -- either from natural sunlight or a tanning bed. It is difficult to determine a safe amount of tanning exposure because several variables must be considered. These factors include a person's skin type (a darker-skinned person's pigment protects their skin from UV damage more than a lighter-skinned person's pigment), quantity of UVA/UVB exposure from a specific tanning bed and medications that can make a person more sensitive to UV exposure. In general, a person should limit exposure to UV radiation to help prevent skin cancer and premature skin aging.

Although UVB is important in the synthesis of vitamin D in the skin, using a tanning bed is not optimal for vitamin D synthesis because most tanning beds predominantly emit UVA, not UVB. While there is some debate surrounding the risks and benefits of UV exposure for vitamin D deficiency, a simple way to prevent or treat vitamin D deficiency is to take a daily vitamin D supplement.

UV radiation suppresses the immune system, which can improve psoriasis and eczema. Given the risk of developing skin cancer, though, a person with psoriasis or eczema should consult with a physician to discuss the risks and benefits of UV light treatment versus other medical treatments. Because no evidence suggests that UV exposure improves acne, talk with a physician to discuss other medical treatments for acne.

No evidence exists that seasonal affective disorder improves with tanning bed use. While some evidence indicates that tanning bed use releases endorphins that may improve mood, frequent tanners showed symptoms of addiction. Opiate blockade in frequent tanners has led to symptoms of withdrawal. A study in which frequent tanners could tell the difference between a non-UV and a UV tanning bed and preferred the UV tanning bed provides additional evidence of addiction.

The potential addiction and increased skin cancer risks that tanning poses are similar to the increased cancer risk of smoking. A public policy agenda on a statewide level now seeks to promote laws that limit exposure of minors to tanning salons, similar to laws limiting access of tobacco to minors. In addition to state laws, proposals have reached the federal level to limit access of minors to tanning salons.

In conclusion, the answer to the question "To tan or not to tan" is: Do not tan! Tanning beds are not a safer alternative to sun exposure.

Julia Ai, MD

Julia Ai, MD, (pronounced Eye) and her Bella Dermatology medical practice are located at Vista Medical Terrace, 2345 E. Prater Way, Suite 205, Sparks. Dr. Ai offers skin cancer screenings, allergy patch testing, treatment and surgery for skin cancer and other skin diseases along with a full spectrum of cosmetic dermatology services. For more information or to schedule an appointment, please call 331-2882.

Northern Nevada Medical Center 2375 E. Prater Way, Sparks, NV 89434 775-331-7000