July 30, 2008 -- As a teen, Rachel Peterson spent much of her time perfecting her tan by hitting up indoor tanning beds from three to four months out of every year.
"I could say at one point I was tanorexic," she told "Good Morning America."
But at just 18, all that tanning caught up with her when she was diagnosed with melanoma, the deadliest form of skin cancer.
"I didn't expect it to happen to me," she said. "I thought it would happen to older people."
Luckily for Peterson, doctors were able to remove the cancerous mole before the disease spread. But many other teenagers are not so lucky.
The rate of melanoma in children 18 and under increased 84 percent from 1975 to 2005. Doctors say the probable cause is exposure to ultraviolet light, both from direct sunlight and indoor tanning beds. The Department of Health and Human Resources has actually classified ultraviolet light as a known carcinogen.
Yet still more than a million people a day go to tanning salons, most of them young women.
Whether people are tanning indoors or outdoors, there are some basic safety concerns sun lovers should know.
Dermatologist Dr. Doris Day was on "Good Morning America" today to help sort out summer dos and don'ts to keep skin healthy.
Do: Avoid Tanning Beds
The idea that a base tan protects you is not true. You may not burn as quickly, but you are still damaging your skin.
Do: Wear Sunglasses and Hats
The sunglasses should have UVA/UVB protection and they should wrap around and cover the sides as well as the front of the face. For hats, baseball caps do not cut it. Hats should shade your whole face and head.
Don't: Wax or Exfoliate Right Before Sun Exposure
Things like waxing or exfoliating, anything that causes inflammation or redness should be done at least seven days before you go to the beach because if the skin is irritated from doing those things, you could burn more easily. Also, avoid beauty products that could make your skin more sensitive like alpha hydroxy acid.
Do: Avoid Retin-A Products in the Sun
Avoid Retin-A products when out in the sun. If you use Retin-A, it actually makes your skin healthier, but healthier skin is more sensitive to the sun. The thing to do is use Retin-A at night and make sure to put sunscreen on during the day.
Do: Avoid Drinks with Lemon and Celery in Them
Lemons and celery contain psoralen, which is a photosynthesizing chemical. Just by touching them, you are making your skin more sensitive to the sun. You should avoid handling them or wash your hands after touching them when you are out in the sun.