The Science of Ceramides Improves Aging Skin

Ceramides are the major component of the skin’s surface. They protect against moisture loss to keep skin youthful, supple and nourish the skin from within. In this column, we will briefly review the science of ceramides and how they improve aging skin.


In 2014, global sales of ceramides approached $240 million, a figure that is expected to exceed $360 million by 2022, for a CAGR of 5.2%, according to Grand View Market Research. This category is expected to post significant growth during the forecast period, due to changing lifestyles, skin aging problems, and more women entering the workforce, among other factors.


There are nine types of ceramides in the stratum corneum, conveniently named ceramide 1 through ceramide 9, and they account for 40 to 50% of the lipids in this outermost layer.


Ceramides serve as the glue that locks together the surface area of skin cells. They are produced in the granular layer of the epidermis below the stratum corneum. The stratum corneum generates enzymes, which convert phospholipids and other lipids into a mixture of ceramides, cholesterol and free fatty acids. They are waxy lipids found in the outer layer of skin cells that help regulate the water barrier and water-holding capacity in the skin by creating a water-impermeable protective organ to prevent excessive water loss as well as build a barrier against the entry of microorganisms.


Unfortunately, ceramide levels decline as we get older; as a result, upper layers of the skin become noticeably become thinner and develop fine lines. Decreased ceramide levels are also associated with dry skin conditions such as atopic dermatitis, eczema and psoriasis. The good news is that by replenishing lost ceramides, skin is able to fortify itself and retain optimal moisture for a firmer, smoother look. Bi-layer forming lipids such as ceramides would impart the most optimum dry skin relief.


Ceramides play an important part in cellular signaling such as regulatory differentiation, proliferation and programmed cell death. It is the main component of the stratum corneum of the epidermis. There are three types of lipids in stratum corneum; ceramides, fatty acids and cholesterol. These are lipids that spontaneously arrange in multiple bi-layers between and around the corneocytes. They create a resistant barrier to water. There has been a lot of research done to find methods to enhance the delivery of actives through the stratum corneum and as a result, many penetration enhancers have been developed for this purpose. There is some debate about how effective topical delivery system of ceramides. This is because it is very difficult for ceramides to travel through the layers of the skin. However, research indicates that substances can travel through hair follicles and pores, reach the growing levels of skin and improve the health of skin cells.


Improving Penetration

Ceramides are expensive ingredients and are usually found in higher-end skin care lines. But natural ceramides are very unstable substances and very costly to obtain, so synthetic ceramides are frequently used. Unfortunately, synthetic ceramides do not penetrate the skin as well as natural ceramides. Ceramide penetration improves substantially if the ceramides are integrated in liposomes.


There are basically four stratum corneum-modifying cosmeceuticals: ceramides, cholesterol, urea and lactic acid. Ceramides are important to skin because they are an essential part of the lipid barrier. Most companies claim that applying ceramides to the skin or taking ceramides orally can, generally speaking, hydrate dry skin, renew, repair and firm aging skin and fill in lines and wrinkles. However, there are not enough clinical studies supporting these claims. Still, many companies are touting the benefits of ceramides.


Since 1990, Elizabeth Arden has marketed a variety of expensive ceramide products as “anti-aging.” Kao claims that its ceramide-based Curel products replenish and repair skin by forming a protective barrier. CeraVe claims its ceramide-based product helps repair, replenish and protect the skin barrier to leave skin looking and feeling soft, clean and healthy.


Manufacturers of phytoceramide pills claim that their products go from the gut into the bloodstream and then to the skin to penetrate it from the inner cells to the outer stratum corneum. Via this route, it is claimed that ceramides can reach the skin’s lower cells and upper layers to support elastin and collagen production to keep skin firm, perform their role in renewing skin cells from the inside out and integrate between the cells of the stratum corneum to keep the skin hydrated.


The long-time use of ceramides in Japan and their safety data played a part in their approval by the US FDA. Clinical studies have shown promising benefits of ceramides in treating atopic dermatitis. There are few clinical studies, however, that clearly prove the benefits of either topical ceramides or oral phytoceramides in normal and aging skin.


Ceramides are derived either from animal sources, such as cows or they are mostly extracted from sweet potatoes, whole-grains such as wheat, and brown rice. Wheat derived ceramides are used in many popular beauty drinks and nutritional supplements. It is helpful to know how ceramide appear on labels. It appears as ceramide PC-102 (Hydroxypropyl bislauramide MEA), ceramide PC-104, ceramide PC-108, ceramide 1, 2, 3, 111, 6-11, etc.


Long-Term Benefits

Ceramides are natural components of human skin. No one can dispute that many Asians look younger than their age; which is due, in part, to a rice-rich diet. This may be a contributor, because of the effects of eating natural phytoceramides contained in the rice. No wonder ceramides provide skin benefits from oral supplements and topical application. There is extensive medical evidence supporting their potential for promoting the development of healthy skin cells.


Overall, skin care products containing ceramides appear to be safe and effective, but more clinical studies are needed to prove the benefits as claimed.

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Navin M. Geria
Chief Scientific Officer
AyurDerm Technologies, LLC
navin@AyurDerm.com

Navin Geria, former Pfizer Research Fellow is a cosmetic and pharmaceutical product development chemist and the chief scientific officer of AyurDerm Technologies LLC, which provides Ayurvedic, natural and cosmeceutical custom formulation development and consulting services to the spa-wellness-dermatology industries. He has launched dozens of cosmeceutical and ayurvedic anti-aging products. Geria has more than 30 years of experience in the personal care industry and was previously with Clairol, Warner-Lambert, Schick-Energizer, Bristol-Myers and Spa Dermaceuticals. He has nearly 20 US patents and has been published extensively. Geria edited the “Handbook of Skin-Aging Theories for Cosmetic Formulation Development” focus book published in April 2016 by Harry’s Cosmeticology. He is a speaker, moderator and chairman at cosmetic industry events.