First, a quick Anatomy lesson: The skin barrier is called the epidermis, which is the outermost layer of cells on the skin. It sits above the dermis, which houses the blood vessels, sweat glands, nerves, and, importantly, the collagen and elastin, the two structural proteins that give skin firmness and bounce. Beneath that is the subcutaneous layer, which is primarily made up of fat to give skin a little cushion. 

“The role of the epidermis is to protect the skin from any sort of foreign substance, whether it be bacteria or chemicals,”

“The epidermis also works to prevent water loss and keep the skin hydrated.”

The skin barrier has a unique structure to help pull this off. “The epidermis is composed of cells — mostly dead skin cells towards the top — and a lipid matrix surrounding these cells,”  “The lipid composition of the epidermis functions to reduce transepidermal water loss.”

Your skin barrier is essential for good health and needs to be protected in order to function properly.

What Is a Damaged Skin Barrier?

Every day, your skin confronts a barrage of threats, many of which come from outside your body and a few that come from within.

The most common causes of a damaged skin barrier are:

• Genetics
• Age
• Aggressive skincare habits, such as over washing and over-cleansing
• Environmental aggressors, like UV exposure and pollution
• Steroids
• Psychological distress

1. Genetics — these include certain conditions like atopic dermatitis, also known as eczema, which is an inflammatory skin condition accompanied by a weak skin barrier. That keeps it from functioning properly, which in turn leaves skin dehydrated and vulnerable to infection.
2. Age is also a contributor since your ability to produce oil wanes over time. This makes it harder to replenish the lipids that are so essential to the integrity of the skin barrier.
3. The external factors. an environment that’s either too humid or too dry. allergens, irritants, and pollutants, too much sun exposure.
4. A common offender is over-cleansing. By cleansing too often or with ingredients that are too aggressive, you can strip the skin of its natural oils. (An easy way to tell is if your skin feels squeaky-clean or tight after you rinse.) That could damage the lipid matrix in your skin barrier. The more intense counterpart to over-cleansing is over-exfoliation, in which — you guessed it — you exfoliate too frequently or with too-harsh materials.

5. Chemical exfoliants, while excellent at removing dead skin cells from the surface of skin, could potentially damage the live, healthy cells in your skin barrier if the concentration is too high. (And don’t even get us started on products that exfoliate via some types of alcohol or essential oils — they’re a recipe for disaster.) Meanwhile, mechanical exfoliants, such as scrubs or other abrasives, can create microtears in the skin, which, not surprisingly, also harms the skin barrier.