Ceramide moisturiser is a skincare product formulated with ceramides — naturally occurring lipid (fat) molecules that make up a significant part of the skin's outer layer, the stratum corneum. Think of ceramides as the "mortar" that holds skin cells (the "bricks") together, forming a protective barrier that locks in moisture and keeps irritants, pollutants, and bacteria out. As we age, or due to factors like harsh weather, over-cleansing, sun exposure, and conditions like eczema or psoriasis, our skin's natural ceramide levels deplete. This leads to a weakened skin barrier, resulting in dryness, flakiness, redness, sensitivity, and increased water loss (known as transepidermal water loss or TEWL). Ceramide moisturisers replenish these lost lipids, helping to restore and strengthen the skin's barrier function.