Before spring break, sophomore Kristen Libolt headed to the tanning salons two to three times a week. Like many, she considered it a preparation for spring break.

Libolt has not gone tanning since, though she said that during the summer she lies out in the sun about three times a week and goes to the tanning bed every few weeks.

"I like being tan," Libolt said. "I think it just makes me feel like I look better when I'm tan."

Libolt was one of many students who hit the tanning salons before spring break seeking a "base tan." She is among the even more students who lie out every spring and summer despite health warnings that excessive tanning causes skin cancer.

Robin Hornung is an associate professor of pediatrics in the UW School of Medicine. Hornung and a colleague conducted a survey of 385 students and discovered that tanning can be addictive.

For the survey, the researchers used the CAGE questionnaire, which has been used to detect alcohol and drug addiction. Hornung said the questionnaire is 60- to 90-percent predictive of addiction. About 12 percent scored positively, meaning he or she answered affirmatively to at least two questions, she said.

The majority of respondents — 75 percent — said they did it to look better. About 41 percent said they went tanning to relax.

Sunbathers' claims may be legitimate — people may experience endorphin releases when they tan, and they may also be more relaxed, Hornung said.

"The biggest issue is that sun tanning became so popular over the last 50 years, and that's why we're seeing this huge rise in skin cancer," Hornung said.

One hundred years ago, being pale was considered the standard of beauty, she said.

In Hornung's survey, 34 percent of respondents said they tanned for a base tan.

"What a base tan is referred to is a set color that you get to where your skin is prepared enough," Neghin Zargar, an employee at Electric Beach Tanning, said. "Darker skin doesn't burn as easily and is more likely not to burn. You want get a base tan to get some color on your skin so that you don't burn."

Hornung said that base tans are more of a myth.

"Getting a tan is not very protective of future sun tanning," she said. "It's equivalent to an SPF of 2."

There are different types of tanning beds, some which are more protective of UV rays than others, Zargar said.

The Matrix bed filters out UV rays, giving a lasting tan. It takes longer but doesn't burn, Zarger said. It is the UV rays that are harmful to skin and could cause cancer.

Zargar said that The Matrix is the bed most of Electric Beach Tanning's regular, older customers use.

"Our most popular beds here are our Star Power," she said. "Those block about 50 percent of our UV rays."

Libolt said that she uses the conventional beds.

"It's just faster, but they're more expensive," she said. She said she is aware of the dangers of tanning.

"I do know that it causes skin cancer, but it's never stopped me [and] I don't know why," she said. "I know that [tanning] is a factor in [skin cancer], but you can get cancer from a lot of things."

Zargar said the decision comes down to a personal choice, comparing it to smoking and alcohol, two things people know are bad but do anyway.

"I think people need to start looking at the odds of these things happening," Hornung said. "I think it's really hard for some people to quit. That's the type of population that may be more difficult to reach."

For those who want to achieve a tan without the harmful UV rays, self-tanning creams are a better choice.

"It's better because certainly self-tanning creams are not carcinogens," Hornung said. "One out of five people are going to get skin cancer. [There is a] gigantic shift in this rising epidemic of skin cancer."

Reach reporter Ninette Cheng at features@thedaily.washington.edu.