Sun protection agents did not demonstrate any protective effect against cancer in this study. The incidence rate among sailors that worked on deck was less frequent and when it did appear, it usually occurred on covered body parts. The lowest number of melanoma incidence occurred among sailors that worked alternatively above and below deck. Thus, moderate sun tanning was not found to be harmful. Moderate sun tanning is not only looks good, but statistics show it can reduce your risk of skin cancer and other maladies including osteoporosis.
Tanning is a defensive mechanism.