What is a crucial factor that influences the longevity of a tan?

Proper hydration is essential for maintaining the longevity of a tan. When the skin is well-hydrated, it retains moisture and elasticity, which can help to keep the outer layer of skin healthy and vibrant. Hydrated skin is less likely to flake or peel, which can often occur when the skin becomes dry. This peeling can lead to a loss of the tan, making it appear uneven and faded.

When skin is adequately moisturized, the tanning agents in lotions can also be more effective, as they will adhere better to hydrated skin. In contrast, if the skin becomes dry or dehydrated, the tan can fade more quickly due to the natural shedding of skin cells. Therefore, maintaining proper hydration both internally (by drinking enough water) and externally (through moisturizers) plays a crucial role in prolonging the appearance of a tan.