Skin Cancer

• UV radiation damages the skin cells, making them more prone to developing skin cancer. According to the American Academy of Dermatology, individuals exposed to UV radiation from indoor tanning have a 75 percent higher chance of catching skin cancer. In addition, studies conducted by the Skin Cancer Foundation found that suffering from just one bout of sunburn -- in which the skin becomes inflamed from overexposure to UV rays from the sun -- can double one's risk of developing melanoma, which is a particularly deadly form of skin cancer.
  
  

Immune System Suppression

• Tanning also comes with the risk of immune suppression, in which one's body loses the ability to effectively produce natural defenses against viruses and infections. According to the World Health Organization, all people, regardless of ethnicity and skin color, are susceptible to this condition. However, it's even worse for those with Herpes simplex virus, in that the suppression could potentially so weaken the individual's immune system that her body cannot effectively handle the virus anymore. This would in turn result in the reactivation of the virus and frequent cold sores.
  
  

Premature Aging

• According to the American Academy, UV rays can alter the DNA of one's skill cells, causing them to prematurely age. What happens is that the radiation damages the skin's collagen, causing it to lose its elasticity. This in turn can result in the development of enlarged pores, age spots, droopy skin and wrinkles. In particular, the collagen in a person's skin goes down during the first 24 hours after tanning, after which it returns to normal, though there is a slight degree of irreversible damage. Repeated and excessive tanning worsens this damage, causing one's skin to gradually develop a texture similar to leather.
  
  

Additional Complications

• Indoor tanning poses slightly more risks than outdoor tanning, in that an improperly disinfected tanning booth can lead to the spreading of sexually transmitted diseases and staph infections. Furthermore, according to the World Health Organization, 20 percent of all known cases of cataracts occur as a direct result of tanning without using protective eyewear.