Sun tanning or tanning is the process whereby skin color is darkened or tanned. It is most often a result of exposure to ultraviolet (UV) radiation from sunlight or from artificial sources, such as a tanning lamp found in indoor tanning beds. People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing. Some people use chemical products that can produce a tanning effect without exposure to ultraviolet radiation, known as sunless tanning.
A visible tan line on a woman whose skin has been darkened by ultraviolet exposure, except where covered
A sun tanned arm showing browner skin where it has been exposed
Photoaging of a woman
Cross-sectional view showing skin tone becoming darker due to the production of more melanin to overcome DNA damage caused by UV radiation
Human skin color ranges from the darkest brown to the lightest hues. Differences in skin color among individuals is caused by variation in pigmentation, which is the result of genetics, exposure to the sun, disorders, or some combination thereof. Differences across populations evolved through natural selection or sexual selection, because of social norms and differences in environment, as well as regulations of the biochemical effects of ultraviolet radiation penetrating the skin.
Extended Coloured (Afrikaans: Kleurlinge or Bruinmense) family from South Africa showing some spectrum of human skin coloration
Former Chief Justice of India, P. Sathasivam, has vitiligo
A suntanned arm showing darker skin where it has been exposed. This pattern of tanning is often called a farmer's tan.
