WHY DOES THE SKIN BECOME DRY?

"Dry skin" (also called xerosis) is skin with a surface lacking in suppleness and softness. It is no longer smooth but rough to the touvh, even course and it has reduced suppleness. It peels lightly (this is called desquamation) and we therefore see small thin flakes on the surface that resemble little scales.

This dryness causes skin discomfort, tightness, tingling and even itching.

There are several causes: 

• External aggression, which fall includes two categories:
  • Chemical factors (soaps, antiseptics, detergents, hard water). Cleansing products that can alter the hydrolipidic film on the surface. This delipidating effect dehydrates the skin. Some strong, stripping soaps can even remove the hydrolipidic film. Skin dryness can therefore be linked to unsuitable hygiene products.
  • Climatic factors (wind, cold, heat, UV radiation). In the winter season, cold dry winds trigger:
    • An alteration of the hydrolipidic surface film 
    • An increase in transepidermal water loss
    • An alteration to the desquamation process: the cold inhibits the activity of certain enzymes responsible for desquamation. The skin becomes dry and scaly. The cornified layer is altered, it can no longer fulfill its barrier function and maintain hydration in the epidermis.
    • An alteration of blood circulation in the skin. In the summer, dry heat causes dehydration of the upper layers of the epidermis, by increasing the evaporation of water from the skin.

• Aging skin.
  • Dry skin is a common sign of aging skin. Its incidence in the population aged over 65 is estimated at around 75%. The skin of older people typically has a thinner epidermis and slower cell renewal. Menopause, which is characterized by a hormone dysfunction, is also responsible for accelerating chronobiological aging.

• Certain skin diseases