If you're like most skincare enthusiasts, you obsessively research about the best skincare practices, the most effective ingredients and right way to layer all your skincare products to get the optimal results. In doing so, you have probably already come across the term "moisture barrier." To be more specific, dermatologist Dr. Anna Guanche explains to Allure that the skin barrier is the fifth and outermost layer of the epidermis called the stratum corneum. It's made up of ceramides, cholesterols and fatty acids and it's the layer that actively sheds dead skin cells. To put it very simply, it works to keep the good stuff in and the bad stuff out.

External factors that affect the skin or moisture barrier are environmental stressors like pollution, the sun's harmful rays, blue light or even too much wind. Internally, drinking too much alcohol and caffeine and not enough water affects it. Obviously, not using enough moisturizer directly affects the moisture barrier.

Damaged Skin Barrier

How would you know if your skin barrier is compromised? The signs are usually confused with rosacea, acne, or sun damage. Dr. Howard Murad, founder of Murad Skincare, tells Glamour UK to watch out for increased breakouts or rashes, redness, itchiness, tightness, flakiness and skin that is rough to the touch. This is because when the skin barrier is compromised, the skin produces more oil and excess oil can make the pores swell. It then traps the excess oil, bacteria and dead skin cells that inflames the skin and results in acne breakouts. Harsh acne-fighting ingredients then dry out the skin and this all becomes a cycle of skin damage.

Overexfoliation is also a major culprit. Many have come to love retinol, alpha hydroxy acids (AHAs) and beta hydroxy acids (BHAs). While chemical exfoliants produce excellent results, the ingredients are potent and can mess with cell turnover. Pamela Marshall, clinical aesthetician and co-founder of Mortar and Milk, advices using the gentler polyhydroxy acids (PHAs) for exfoliation and to supplement it with skin-balancing niacinamide.

Also read: Why Polyhydroxy Acid Is the Best Chemical Exfoliant for Sensitive Skin

How to Protect the Skin Barrier

The most crucial step is to make sure that skin is hydrated. It's a common misconception that oily skin doesn't need moisturizer and that's not true. Even if skin is oily, Dr. Murad says that your still need to restore moisture and keep hydration levels steady. The best ingredients to rehydrate skin are hyaluronic acid and ceramides. Try La Roche-Posay Hyalu B5 Pure Hyaluronic Acid Face Serum and CeraVe Moisturizing Cream. Dr. Murad adds that antioxidants and anti-inflammatories like vitamins A, C and E are also crucial for skin repair. 

The skin or moisture barrier can be tricky to repair if you have severe skin damage or an underlying skin disease. If you've taken steps at home that are not lessening symptoms like itchiness, flakiness and roughness, Dr. Guanche suggests visiting a dermatologist and have your barrier function analyzed. The dermatologist will use a measurement called Transepidermal Water Loss (TEWL) and will help you figure out the best skincare routine to repair your moisture barrier. In the meantime, keep moisturizing and take it easy on the chemical exfoliants.

Related article: Bakuchiol: The Gentler Alternative to Retinol