You have probably seen ceramide products listing specific types: ceramide NP, ceramide AP, ceramide EOP, or older labelling as ceramide 1, 2, 3. The numbering system has been updated since 2010, which is part of why the labelling is confusing. But more importantly, do the specific types actually matter for the person shopping for a moisturiser?
What ceramides are and why they matter
Ceramides are sphingolipids, a class of lipid molecules, that make up approximately 50% of the stratum corneum by weight. Together with cholesterol (25%) and free fatty acids (15%), they form the lamellar bilayer structure between skin cells that controls water loss and acts as the primary physical barrier against external irritants, pathogens, and allergens.
When ceramide levels in the stratum corneum are depleted, the barrier becomes permeable. Transepidermal water loss increases (the skin becomes dry), and the skin becomes more reactive to irritants that would not normally penetrate. This is the core pathology in atopic dermatitis: research consistently shows significantly reduced ceramide levels in eczema-affected skin compared to healthy controls, and restoring ceramide levels through topical application improves barrier function and reduces symptoms.
This is not only relevant for eczema. Age, harsh cleansing, over-exfoliation, and environmental stress all reduce ceramide levels in skin. Anyone with dry, sensitive, or barrier-compromised skin has a practical reason to use ceramide-containing products.
The naming system
The old naming system (ceramide 1, 2, 3 through 9) was replaced by an INCI system in 2010. The new nomenclature describes ceramide structure: the first part describes the sphingoid base (A for dihydrosphingosine, N for sphingosine, P for phytosphingosine) and the second part describes the fatty acid (EO for ester-linked omega-hydroxy fatty acid, O for omega-hydroxy, H for hydroxyl, N for non-hydroxy).
So the old ceramide 1 is now ceramide EOP, ceramide 2 is ceramide NP, ceramide 3 is ceramide NP as well (there was duplication in the old system), and ceramide 6-II is ceramide AP. You may still see both old and new naming on products from different periods.
The most biologically important ceramides for the skin barrier are ceramide NP (the most abundant in healthy skin), ceramide AP, ceramide EOP, and ceramide NS. Together, these cover the major subtypes present in the normal stratum corneum.
Do the specific types matter?
Yes, but in a way that is more relevant to formulators than to consumers. The key finding from barrier research is that ceramides work most effectively in combination and with the correct accompanying lipids. A formula that includes ceramide NP alone is less effective at barrier repair than one that includes a physiologically relevant combination of ceramide NP, ceramide AP, ceramide EOP, cholesterol, and fatty acids (linoleic and palmitic acids) in approximately the right ratios.
A 2006 study by Chamlin et al. in the Journal of the American Academy of Dermatology compared a ceramide-dominant barrier repair formulation to other moisturisers for childhood atopic dermatitis and found the ceramide formula significantly superior for reducing TEWL and improving symptoms. The ceramide formula in that study used a combination of ceramides including NP, AP, and EOP alongside cholesterol and fatty acids.
Single-ceramide products have been shown to have limited barrier repair effect. The three lipid categories (ceramides, cholesterol, fatty acids) must all be present in a roughly 1:1:1 molar ratio to efficiently form the lamellar bilayer structure. This is the practical implication of the research: combination ceramide products with accompanying lipids are more effective than single-ceramide formulas regardless of which specific ceramide type is present.
What to look for on an ingredient label
When evaluating a ceramide product, look for:
- Multiple ceramide types listed (ideally ceramide NP, AP, and EOP as the core three)
- The presence of cholesterol and fatty acids (linoleic acid, palmitic acid) alongside ceramides
- Ceramides appearing in the first half of the ingredient list, not as last traces
- Humectants (glycerin, hyaluronic acid) alongside ceramides for hydration as well as barrier repair
The most effective ceramide products in the clinical literature have typically used a three-lipid system mimicking the natural barrier composition, not just added ceramides to an existing cream formula. CeraVe’s proprietary MVE delivery system and Eucerin’s ceramide formulas are the most-studied examples, though numerous natural skincare formulations now incorporate ceramide complexes with similar rationale.
Natural sources of ceramides
Plant-derived ceramides (phytoceramides) come from wheat germ, rice bran, sweet potatoes, and other plant sources. They are structurally similar but not identical to human ceramides. Research shows they do function in the barrier: a 2014 study in Nutrients found oral phytoceramide supplementation improved skin hydration and reduced TEWL compared to placebo. Topically, plant ceramides incorporated into barrier-repair formulas perform similarly to synthetic ceramides in most studies.
For consumers, the specific ceramide numbers are less important than whether the overall formulation is designed around the principle of barrier repair: multiple lipid types working together, at meaningful concentrations, with appropriate accompanying humectants and emollients. That is the question to answer when choosing a ceramide moisturiser.