The lips are among the most delicate areas of the body. The skin there is indeed very thin, about five times thinner than the rest of the face, and the dermis hardly houses any sebaceous or sweat glands. Therefore, the lips are almost not protected by a hydrolipidic film, a mantle that acts on the rest of the body as a barrier sheltering the skin from external aggressions and preventing water loss. They also contain a low amount of ceramides compared to the rest of the body. Thus, the lips are particularly vulnerable to cold and very prone to dehydration, which can lead to chapping.
The first step in taking care of one's lips is to hydrate and nourish them regularly.
The ceramides found in certain cosmetics are good candidates for this. Indeed, these lipids, which make up the intercellular cement of the corneal layer, are known for their nourishing benefits and their ability to retain water in the epidermis. More specifically, ceramides occupy the space between each of the cells in the corneal layer, which helps to hold the corneocytes together. These lipids thus improve the skin's barrier function and prevent water from evaporating from skin cells. This property of ceramides is particularly useful for lip care and is found in topical treatments that contain them. Indeed, several studies show that after application of a cream rich in ceramides, the levels of endogenous ceramides are increased.
Furthermore, some research suggests a healing role of ceramides, potentially beneficial for soothing chapped lips. Studies conducted in vitro and on murine models have indeed shown that these active ingredients are capable of modulating the concentration of eicosanoids, molecules involved in the regulation of inflammation and the healing process. This rebalancing allows for accelerated wound closure and stimulates the migration of fibroblasts, the cells that produce collagen. This collagen is essential for the formation of granulation tissue, a temporary structure produced following an injury. These regenerative effects of ceramides could benefit the lips, which are often prone to chapping.
It is noteworthy that several clinical studies have been conducted with products containing ceramides to highlight their benefits for the lips. One such study involved 31 volunteers who applied a 2% pseudo-ceramide lip balm four times a day. Pseudo-ceramides are synthetic molecules designed to mimic the structure and properties of natural ceramides. After four weeks, researchers noted a 65% improvement in the softness of the participants' lips, a 25% decrease in water loss and an overall increase in the amount of ceramides in the stratum corneum, across all types. Another study was conducted with 105 people. After a single application of a ceramide-enriched lip balm, 97% of participants found their lips to be more hydrated and, for 98%, they appeared plumper.
Ceramides are hydrating, nourishing, and healing agents that are beneficial for lip care.