Ceramides

Ceramides are a family of lipid (fat) molecules that make up approximately 50% of the stratum corneum — the outermost layer of skin. Alongside cholesterol and fatty acids, they form the lamellar bilayer structure that serves as the skin's primary moisture barrier. This barrier prevents transepidermal water loss (TEWL) and stops environmental irritants, allergens, and pathogens from penetrating the skin.

There are nine major types of ceramides (Ceramide 1 through 9, or EOS, NS, NDS, EOP, NP, AP, AH, NH, AS in scientific nomenclature). Healthy skin requires the right ratio of all types. A deficiency in any — caused by ageing, harsh cleansers, over-exfoliation, or conditions like eczema — disrupts the barrier.

A damaged ceramide barrier shows up as dryness, flaking, tightness, redness, and sensitivity to products that were previously tolerated without issue. In more severe cases — atopic dermatitis (eczema) and psoriasis — ceramide deficiency is a primary driver of the condition rather than just a symptom.

Common causes of ceramide depletion include: over-cleansing with surfactant-heavy or alkaline soaps, over-exfoliation with AHAs or retinol, cold and dry weather, ageing (ceramide production declines with age), and excessive sun exposure.

SkinCeuticals Triple Lipid Restore 2:4:2 is the most clinically validated ceramide replenishment product available in South Africa. It contains ceramides 1 and 3, cholesterol, and fatty acids at the optimal ratio to mimic the skin's natural barrier composition. Studies show measurable improvement in skin hydration, density, and reduction of TEWL within 4 weeks.

Ceramide-containing products are best applied to slightly damp skin as part of the final moisturising step in both morning and evening routines. They can be layered under heavier occlusive creams for very dry skin. Critically, they can be used alongside all active ingredients — in fact, they are strongly recommended when using retinol or AHAs to buffer irritation and prevent barrier breakdown.