Serine

What Is Serine?

Serine is a non-essential amino acid that is a key component of the skin's Natural Moisturizing Factor (NMF). It plays a critical role in maintaining stratum corneum hydration by binding water molecules. Serine is also a precursor to ceramide synthesis (via sphingosine pathway), making it important for barrier lipid production. Found naturally in high concentrations in healthy skin — levels decline with age and in dry skin conditions.

Key Skin Benefits

• + Essential NMF component — maintains skin hydration
• + Ceramide precursor — supports barrier lipid synthesis
• + Binds water in stratum corneum
• + Levels naturally decline with age — replenishment beneficial
• + Non-irritating — naturally present in healthy skin

Pros

• + + Natural NMF component
• + + Supports ceramide synthesis
• + + Excellent safety profile
• + + Affordable and stable
• + + Works in hair and skin formulations

Cons

• − − Not a stand-alone active — works best in amino acid blends
• − − Limited visible benefits as monotherapy
• − − Heat-degradable

Specifications

Safety Ratings

Regional Regulatory Limits

Typical Usage % by Product Type

References

1. Rawlings AV, Harding CR — NMF and skin moisturization. Dermatol Ther (2004). PMID: 15113286
2. Nakagawa N et al. — Amino acids in stratum corneum. J Invest Dermatol (2004)
3. Fluhr JW et al. — NMF and skin hydration. Exp Dermatol (2008). PMID: 18631469