True or False? Outdoor Tanning Causes Skin Cancer
True. The tanning industry's focus on melanoma only is misleading, says Fisher, noting that the link between non-melanoma skin cancer and UV exposure is solid.
Multiple studies have demonstrated a relationship between UV exposure and an increased risk of developing skin cancer, according to a report published in the May 2008 Journal of the American Academy of Dermatology, although the specifics of the association are different for melanoma and the non-melanoma skin cancers, squamous cell and basal cell.
True or False? You Need Sunlight to Get Enough Vitamin D
False. No one's disputing that exposure to sunlight produces vitamin D, "the sunshine vitamin," or that vitamin D isn't important. A spate of recent studies has found that adequate levels of vitamin D may lead to improved heart health and protect from breast cancer, among other long-known benefits such as bone health.
"I have no argument on the potential benefit of vitamin D," Fisher says.
Limited exposure to natural sun -- exposing skin to about 2 to 10 minutes a day without sunscreen -- is recommended by some experts as a way to produce enough vitamin D, but Fisher and others don't agree that's best. "There is no need to get your vitamin D from UV radiation," Fisher says. "You can get it from a pill." Many foods are also fortified with vitamin D such as milk.
Brandith Irwin, MD, a Seattle dermatologist and spokeswoman for the American Academy of Dermatology, agrees. "It's easy to supplement without tanning," Irwin says. Even with sunscreen on, she says, you may produce some vitamin D. "No sunscreen blocks all UV rays."
But depending on where you live, limited sun exposure won't always produce enough vitamin D, she says. "In many parts of the country, you could lay out without sunscreen for an hour and not get enough vitamin D production," Irwin says.
Irwin says vitamin D replacement can be easily obtained via an inexpensive supplement -- without risk to your skin.
Dietary sources include milk, cereal, yogurt, and orange juice fortified with vitamin D as well as salmon, mackerel, and tuna.
The Food and Nutrition Board of the Institute of Medicine recommends as an adequate vitamin D intake 200 IU for adults 19 to 50, 400 IU for adults 51 to 70, and 600 IU for those 71 and older.
But in 2007, a team of researchers published an editorial in the American Journal of Clinical Nutrition suggesting that daily intakes of about 1,700 IU would be better to ensure an adequate blood level of vitamin D.
True or False? Tanning Causes Premature Aging of the Skin
True. Whether the exposure is indoors or outdoors, ultraviolet exposure over time causes what doctors call "photo aging," or wrinkles and a leathery look.
German researchers evaluated 59 people who voluntarily started to use sun beds over a three-month period. Use of the sun bed induced a DNA mutation in the skin known to be linked with photo aging, they report in the Journal of Investigative Dermatology.
In another study, published in Aging Cell, ultraviolet radiation exposure from the sun was found to speed the accumulation of DNA mutations in human skin associated with premature aging.
To help prevent cancer and premature aging, experts recommend that you:
- Wear a broad spectrum sunscreen year-round of at least SPF 15 that protects against both UVA and UVB rays.
- Avoid sun exposure between the peak hours of 10 a.m. and 3 p.m.
- Wear protective clothing, such as a broad-brimmed hat and long sleeves.
- Apply sunscreen 30 minutes before going out in the sun and every two hours after while you are exposed.