A quick primer: ceramides are lipid molecules found naturally in our skin. They work to bind skin cells together, sealing in moisture and blocking out harmful microbes. Unfortunately, as we age, our skin produces fewer ceramides, leading to dryness, loss of firmness, and other signs of aging. Enter Dr. Jart Ceramidin Liquid. Packed with a small army of ceramides, this derm-developed formula delivers a powerful dose of moisture, plus ingredients that strengthen and smooth skin for the long haul.