What skin barrier?

It is the outermost layer of your skin, which defends your body against a constant onslaught of environmental threats while simultaneously protecting your body’s critical water balance.

is also called the “brick-mortar” structure—corneocytes as the brick and lipid interface as the mortar. The lipid interface comprises free fatty acids, cholesterol and ceramides.

The primary job of the skin barrier is to keep water-rich internal organs from drying out by preventing water loss in dry environments. Without this protection, the body would not be able to sustain its normal activities, and everything -- from major organs down to the tiniest cells -- would dry out and die. The skin barrier also acts as a sort of dam, keeping too much water from rushing into the body. The barrier provided by the skin allows just enough water to enter the body without flooding it.