1. Urea
Urea is a key humectant in skincare, attracting water from the dermis into the stratum corneum, helping to moisturize dry skin. It contributes significantly to the natural moisturizing factor (NMF) and helps in skin hydration. Urea also has keratolytic properties, easing itching and promoting the shedding of dead skin cells. It helps maintain skin moisture and can reduce transepidermal water loss (TEWL) when combined with occlusive ingredients. Urea also softens hyperkeratotic areas and enhances the skin’s water-binding capacity, making it effective in treating dry and scaly skin.

2. Soft Paraffin
White soft paraffin (Vaseline) is a petroleum-derived ingredient known for its moisturizing and protective qualities. It forms a barrier on the skin to prevent moisture loss and protect against environmental factors like wind and cold. It soothes and softens dry, rough skin, enhances the skin barrier, and reduces TEWL. Suitable for all skin types, it’s often used on lips, elbows, and heels for deep hydration and protection.

3. Mineral Oil
Mineral oil is widely used in skincare for its protective and moisture-sealing properties. It forms a barrier on the skin, preventing moisture loss and softening dry skin. It doesn’t react with the skin, is non-comedogenic, and has a long shelf life. Unlike vegetable oils, it provides physical benefits by locking in moisture and protecting the skin from irritants. Light mineral oils are less occlusive than heavier ones, allowing better skin breathability while still preventing water loss. It also helps improve skin hydration by increasing the thickness of the skin’s outer layer.