Facultative skin color refers to what?

Facultative skin color describes the variability in skin pigmentation that can change in response to environmental factors. This concept is particularly relevant in relation to UV exposure from sunlight. When skin is exposed to sunlight, it produces more melanin, leading to a darker appearance; this adaptation helps protect against further UV damage. This adaptability contrasts with permanent skin conditions, reactions to cosmetic products, or skin diseases, which do not inherently involve changes based on environmental influences. Hence, understanding facultative skin color is essential in the field of skincare as it emphasizes how external factors, such as sun exposure, can have an immediate impact on skin tone.