Why does skin need hydration?

An Essential Physiological Function of the Skin – Moisturization

1. The process of skin aging, from infancy to old age, can essentially be described as a process of continuous water loss.

2. The tenderness of the skin depends on the water content in the stratum corneum of the epidermis, as the skin's moisture level decreases gradiently from the inner to the outer layers.

3. The normal water content of the stratum corneum is 10–20%. When external humidity drops below 60%, the water content in the stratum corneum decreases, leading to skin issues such as dryness.

Therefore, hydration is a crucial fundamental step in daily skincare routines.