Epidermal layer is the outermost layer of skin, only about 0.2 mm thick. Its function on human body is to prevent foreign bodies from invading, filter ultraviolet rays, lock water and cell division and proliferation. It is the protective film of our skin. The epidermis is also divided into five parts, namely the stratum corneum from the outside to the inside. Transparent layer and granular layer; There are spinous layers; Grassroots.

Dermal layer, the second of the three layers of skin, is located between epidermis and subcutaneous tissue, with a thickness of about 0.2 mm, and consists of collagen fibers, matrix, reticular fibers and elastic fibers. Among them, collagen is considered to be the dermal component most closely related to skin aging.

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The stratum corneum of our human body will be renewed every once in a while, which is generally a metabolic cycle every 28 days, so we can see obvious effects to improve the skin condition through a cycle. Less sebum secretion, no greasy feeling, generally fair and delicate skin, but dry skin. Dry skin can't stand external stimuli, such as wind and sun, and it will cause skin flushing, erythema and even burning sensation.

Sensitive skin is a highly intolerant skin condition, which is reflected in the thin stratum corneum and obvious red blood on both cheeks. It is easily stimulated by pollen, climate, temperature, sunshine, improper use of cosmetics and other factors, resulting in tingling, burning, tightness and itching, which is easy to cause allergies. Skin appearance is often accompanied by mild desquamation, erythema and dryness.

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References:

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