Understanding Your Skin Barrier

The skin barrier is the outermost layer of your skin: cells held together by lipids, including ceramides, cholesterol and fatty acids. Its job is to keep water in and irritants out.

It gets damaged by over-cleansing, over-exfoliating, harsh actives and, occasionally, by weather. The signs are tightness, stinging when you apply products, and sudden sensitivity to things that never bothered you.

Repair is simple but slow. Stop actives temporarily, cleanse once a day, and use a ceramide-rich moisturizer twice a day. Two to four weeks is normal.