‌Ceramide‌ is a key lipid component in the skin's stratum corneum. Synthesized from fatty acids and sphingosine, it constitutes over 50% of the epidermal lipids. Ceramide strengthens the skin barrier function, reducing water loss and defending against external irritants. As we age or due to environmental damage, ceramide levels decline, leading to issues like dryness and sensitivity. Skincare products often incorporate ceramides (such as types NP and AP) to repair the barrier. When combined with cholesterol and free fatty acids, they mimic the skin's natural lipid structure, enhancing moisturizing and anti-inflammatory effects. This approach is particularly beneficial for sensitive skin care.