What is the term for the immediate phase of tanning that can fade quickly?

The immediate phase of tanning that can fade quickly is referred to as IPD, which stands for Immediate Pigment Darkening. This phenomenon occurs right after exposure to ultraviolet (UV) light, causing the skin to darken almost instantly due to the oxidation of existing melanin. IPD is a temporary response, and while it may provide a quick change in skin color, it typically fades within hours or days as the skin naturally undergoes its cycle of regeneration and desquamation.

In contrast to IPD, the other terms like "Tanning Base," "Base Tan," and "Skin Glow" refer to different concepts in the tanning process. A base tan is developed over time through repeated exposure to UV light and can provide some level of protection against sunburn. Skin glow, while a desirable effect after tanning, does not specifically refer to an immediate change. Therefore, understanding IPD is crucial for those seeking to understand the stages and types of tanning effects properly.