What is the primary purpose of a moisturizer?

The primary purpose of a moisturizer is to hydrate the skin and maintain its barrier function. Moisturizers contain ingredients that help draw water into the skin and prevent moisture loss, which is essential for keeping the skin plump, smooth, and healthy. Well-hydrated skin is less prone to irritation, dryness, and premature aging, as it supports the skin's natural barrier that protects against environmental stressors.

While creating a barrier against pollutants is a benefit of certain formulations, the main focus of moisturizers is hydration and barrier maintenance. Brightening skin tone and reducing signs of aging may be secondary effects or benefits, but they are not the primary function of a moisturizer. These other characteristics often depend on specific active ingredients in targeted treatments, rather than the fundamental role that moisturizers play in skin care.