Using a tanning bed, booth, or sunlamp to get tan is called indoor tanning. Exposure to ultraviolet (UV) rays while indoor tanning can cause skin cancers including melanoma (the deadliest type of skin cancer), basal cell carcinoma, and squamous cell carcinoma. UV exposure also can cause cataracts and cancers of the eye (ocular melanoma). UV exposure from the sun and from indoor tanning is classified as a human carcinogen (causes cancer in humans) by the International Agency for Research on Cancer (part of the World Health Organization) and by the U.S. Department of Health and Human Services.
Source: www.cdc.gov