If you wash your face with water and feel itchy.You are still using moisturizing skin care products, but the skin is still dry and peeling. The face is often allergic, but no reason can be found. From the appearance, the sub-health state of these skins is mainly caused by impaired skin barrier function.
The skin barrier is the first line of defense for our skin and an important foundation. The skin barrier system is an integral body composed of sebum membrane, keratinocytes and intercellular lipids.The function is two-way. It has external resistance to various harmful invasions,such as antigens, microorganisms and sunlight. It can prevent the loss of water and nutrients in the human body and maintain normal physiological functions.
Some bad habits in life can damage the skin's barrier system easily. The skin will produce unexplained dryness, redness and discomfort. In severe cases, a series of problems will occur, such as scaling, itching, and inflammation. If you have had a history of skin disease, you may relapse.    
There are the six most common skin barrier injuries in life.
Over-cleaning such as using a facial cleanser or makeup remover with a particularly strong degreasing ability.Wash the face repeatedly with a cleaning brush for deep cleaning.
Use inappropriate skin care products, such as skin care products, scrubs, facial masks, and even tri-products that are not suitable for their skin type.
Do not to rub skin cream. Some people only spray moisturizer, but not skin cream.
The excessive use of moisturizing mask, such as too frequent time, each time is too long.
Abuse of hormonal ointment including excessive use, excessive time and no indication of abuse.
Unreasonable beauty treatment will also damage our skin.