Why Some People Cannot Tan?

Pigments called melanin are found on our skin. These pigments are produced by cells called melanocytes and give their skin its color. The amount of melanin in the skin of people with dark skin is higher than that of light-skinned people.

Tanning and sunburn are changes in the skin caused by sun rays. They arise as a result of different processes occurring on the skin according to the wavelength of the ultraviolet rays emitted from the sun.

Melanocyte cells exposed to ultraviolet wavelength (UV) rays produce melanin pigment. Melanin absorbs UVA (ultraviolet rays with a wavelength greater than 315 nanometers) and UVB rays (rays with a wavelength of 280-315 nanometers) to protect the skin from the harmful effects of sunlight. An increase in the amount of melanin causes the skin to darken. UV rays can also cause a change in the structure of melanin pigment. This change, which causes darkening of the skin color, occurs within a few hours after sun exposure and continues for 3-5 days. The darkening in the color of the skin as a result of the increase in the amount of melanin is longer lasting.

Sunburn is caused by the skin being exposed to the sun's rays (especially UVB rays) too much. In sunburn, skin rashes occur as a result of damage to blood vessels close to the skin.

The amount of melanin in the skin of white-skinned people is low, and when they are exposed to sunlight, their skin reddened rather than tanning. Because melanocyte cells cannot produce enough melanin in this type of skin exposed to sunlight. Therefore, people with white skin can not usually tan, instead sunburn occurs on such skin.