Humectants are widely used in dermatology and cosmetic formulations to support and treat dry and/or flaky skin, and their use is strongly supported by scientific evidence. Humectants are ingredients—such as glycerin, urea, hyaluronic acid, and sorbitol—that attract water from the environment and from deeper skin layers into the outer layer of the skin (stratum corneum). By increasing the water content of the stratum corneum, humectants help to maintain skin hydration, improve skin flexibility, and reduce the appearance of dryness and flakiness.

Numerous clinical studies and reviews have demonstrated the efficacy of humectants in improving skin barrier function and alleviating symptoms of xerosis (dry skin). For example, glycerin and hyaluronic acid have been shown in randomized controlled trials to increase skin hydration and decrease transepidermal water loss. Urea, another common humectant, not only hydrates but also has mild keratolytic properties that help with scaling and flaking. The American Academy of Dermatology and other authoritative sources recommend moisturizers containing humectants as first-line therapy for dry and flaky skin.

Overall, the use of humectants for dry/flaky skin is well-validated by scientific research, making them a mainstay in both over-the-counter and prescription skincare products for this condition.