What happens to outer skin cells when tanning occurs?

When tanning occurs, outer skin cells, specifically the epidermal cells, undergo a process in which they accept pigment, primarily melanin. This process is a defense mechanism triggered by exposure to ultraviolet (UV) radiation. The skin responds to UV exposure by producing more melanin, which is deposited in the skin cells to absorb and dissipate the excess UV radiation, thus protecting deeper layers of the skin from damage.

As a result, the skin takes on a darker appearance, which is the visible form of this pigmentation process. The increase in melanin production also helps to provide some degree of protection against future UV exposure. Ultimately, this process is what leads to the tanned look that many individuals seek when they spend time in the sun or use tanning beds.