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Tanning Parlors Take Heat
People who seek a glamorous tan through sun lamps may double their risk of developing Common types of skin cancer，according to a new study that found the risk was highest for those who start at a young age.
The study，appearing in the latest issue of Journal of the US National Cancer Institute，concluded that people who use tanning devices were 1.5to 2.5times more likely to have common kinds of skin cancer than were people who did not use the devices.The study confirmed what doctors have long suspected-that sun lamp use increases the risk of basal cell and squamous cell skin cancers，said Margaret R.Karagas，first author of the study.
Either going to the tanning parlor，or getting an infrequent sunburn can seriously damage the skin，said Dr.James Spencer，vice chairman of the department of dermatology at Mount Hospital，but the small day-to-day exposure is worse for the skin in the long run.
Joseph A.Levy，vice president of the International Smart Tan Network，however，said occasional sunburn ’is a risk factor in all forms of skin cancer and intermittent sunburn is what the tanning industry is trying to stop.’
In the study，Karagas and her colleagues interviewed 603basal cell skin cancer patients and 293with squamous cell skin cancer.They talked to 540control subjects who did not have either type of skin cancer.
About 1million Americans are diagnosed annually with skin cancer.Among those skin cancer patients，about 80percent are with basal cell skin cancer，16percent，with squamous cell skin cancer and 4percent with melanoma-the most serious form.of skin cancers.Back to the interviewed patients，190reported that they had used tanning devices at some time.In the control groups，only 75had used such devices.Karagas said a statistical analysis shows that those who used tanning equipment were 2.5times more likely to get squamous cell skin cancer than those who had not used the devices.For basal cell cancer，the risk was 1.5times greater.
The risk was highest for those who first used the tanning devices before the age of 20，said Karagas.For this group，the squamous cell cancer risk was 3.6times greater than that of the controls while the basal cell cancer risk was 1.3times greater.

The passage confirms that using tanning equipment is harmful to one’s health.（）