what is the meaning of tanning on skin
Sun tanning By the early 20th century, the therapeutic benefits of sunlight began to be recognised.[26] In 1903, Niels Finsen was awarded the Nobel Prize in Medicine for his “Finsen Light Therapy”.[27] The therapy was a cure for diseases such as lupus vulgaris and rickets. Vitamin D deficiency was found to be a cause of rickets, and exposure to the sun would allow vitamin D to be produced in a person. Therefore, sun exposure was a remedy to curing several diseases, especially rickets. In 1910 a scientific expedition went to the island of Tenerife to test the wider health benefits of "heliotherapy",[28] and by 1913 "sunbathing" was referred to as a desirable activity for the leisured class.[29]
Skin It harbors many mechanoreceptors (nerve endings) that provide the sense of touch and heat through nociceptors and thermoreceptors. It also contains the hair follicles, sweat glands, sebaceous glands, apocrine glands, lymphatic vessels and blood vessels. The blood vessels in the dermis provide nourishment and waste removal from its own cells as well as for the epidermis.