What are the benefits of ceramides for the lips?

The lips are among the most delicate areas of the body. Indeed, the skin here is extremely thin, approximately five times thinner than the rest of the face, and the dermis hardly houses any sebaceous or sweat glands. Consequently, the lips are almost not protected by a hydrolipidic film, a mantle that acts on the rest of the body as a barrier shielding the skin from external aggressions and preventing water loss. They also contain a low amount of ceramides compared to the rest of the body. Therefore, the lips are particularly vulnerable to the cold and highly 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 recognised 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 for ceramides, potentially beneficial for soothing chapped lips. Studies conducted in vitro and on murine models have indeed shown that these actives were able to modulate the concentration of eicosanoids, molecules involved in the regulation of inflammation and the healing process. This rebalancing allows for the acceleration of wound closure and stimulates the migration of fibroblasts, the cells that produce collagen. The latter 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 intriguing to note that numerous 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, the researchers noted a 65% improvement in the softness of the participants' lips, a 25% reduction 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 individuals. 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.

It is legitimate to question the potential risks of cosmetic actives, particularly when they are intended to be applied to the skin of the lips. Two concerns frequently arise: can these ingredients be dangerous if they penetrate deeply into the skin or if they are accidentally ingested? Fortunately, the answers are reassuring. The ceramides have an excellent safety profile and are not subject to any restrictions in cosmetics, whether in the European Union (EC), the United States (FDA), Canada (Health Canada) or South Korea (KFDA).

Furthermore, various studies conducted on the safety of ceramides in cosmetics have confirmed their harmlessness and have shown that they do not cause either irritation or systemic effects, even in cases of prolonged use. Patch tests carried out on animals and humans have revealed no adverse skin reactions. Moreover, although ceramides are lipophilic, research indicates that they remain confined to the stratum corneum of the epidermis and do not penetrate into the deeper layers of the skin. Finally, studies conducted on murine models have shown that there are no side effects related to the ingestion of ceramides, which is particularly reassuring, as these active ingredients are frequently present in lip products, where the risk of ingestion, although low, is not non-existent.

• ISHIKAWA J. & al. Variations in the ceramide profile in different seasons and regions of the body contribute to stratum corneum functions. Archives of Dermatological Research (2013).

• BRANDT S. & al. The structure, function, and importance of ceramides in skin and their use as therapeutic agents in skin-care products. American Academy of Dermatology (2014).

• NEUBERT R. & al. Controlled penetration of ceramides into and across the stratum corneum using various types of microemulsions and formulation associated toxicity studies. European Journal of Pharmaceutics and Biopharmaceutics (2014).

• HELDRETH B. & al. Safety assessment of ceramides as used in cosmetics. Cosmetic Ingredient Review (2015).

• YAMAMOTO T. & al. The efficacy of synthetic pseudo-ceramide for dry and rough lips. International Journal of Cosmetic Science (2020).

• CHALFANT C. & al. Ceramide kinase regulates acute wound healing by suppressing 5-oxo-ETE biosynthesis and signaling via its receptor OXER1. Journal of Lipid Research (2022).

• DEVGAN L. Clinical assessment of a topical ceramide and hyaluronic acid based lip treatment in perceived lip aesthetics. The Journal of Clinical and Aesthetic Dermatology (2024).