False.
It is not true that tanning, even excessive tanning, can damage internal organs. Many falsely believe this because of a story (widely circulated on the internet) which describes a young woman trying to get a tan for her wedding. Supposedly this woman visited a number of tanning salons (some versions of the story say up to a dozen) two to three days before her wedding. The excessive tanning then resulted in her internal organs getting “fried”, resulting in her death. As hard as I looked into the medical literature, I couldn’t find a reference to this poor woman, so I feel confident saying the story never happened. Also consider that the rays from tanning beds don’t penetrate the skin more than one sixteenth of an inch. Tanning beds expose users to light bulbs that emit ultraviolet radiation, an artificial light similar to the light you are exposed to when you are out in the sun. Indoor tanning started to become very popular in the 1970’s and is a multi-billion dollar industry today. Because of the billions spent on indoor tanning, the industry is able to hire powerful lobbyists who work hard to block indoor tanning regulations both at the state and federal levels. Currently, only about half the states in this country have regulatory laws. The tanning industry claims that tanning is safe and even beneficial to health. On the other hand, scientific and medical literature paints a much different picture. Levine and colleagues (2005), state that in recent years research has suggested an association between sun bed use and a significantly elevated risk of skin cancer. Additional adverse effects of indoor tanning include skin burn, allergic reaction, eye damage, wrinkles, and damage to blood vessels.
Reference:
Levine J, Sorace M, Spencer J, Siegel D: The indoor UV tanning industry: A review of skin cancer risk, health benefit claims, and regulation. Journal of the American Academy of Dermatology (2005), Vol 53, pps. 1038-1044.