Ingredients

Sodium Lactate

Written by Reviewed by the SYNC editorial team Published Last reviewed Editorial standards

Sodium Lactate — the sodium salt of lactic acid and a key component of the skin's natural moisturizing factor (NMF), the built-in blend that keeps the surface hydrated. As a humectant it draws and holds water in the upper layers of skin, and it also has mild buffering and antimicrobial properties that make it a versatile formulation ingredient. It is commonly paired with other NMF components to boost long-lasting hydration.

Key points

  • Sodium lactate is part of the skin's natural moisturizing factor, so it is well matched to the skin's own hydration system.
  • As a humectant, it attracts water into the stratum corneum to help keep skin soft and supple.
  • It also acts as a pH buffer, helping stabilize the acidity of formulations.
  • At higher concentrations it can feel drying, so it is typically used at balanced levels alongside other moisturizers.

Frequently asked

Is sodium lactate an exfoliant like lactic acid?

No; sodium lactate is the salt form and works mainly as a hydrating humectant rather than as an exfoliating acid, though it can raise skin sensitivity to sunlight.

Why is sodium lactate added to soaps and lotions?

It boosts moisture retention and can improve the feel and firmness of a formula, which is why it appears in many hydrating products.

Related topics

This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.

Encyclopedia

Further reading

This entry was written and checked against the sources below. They are published by clinical and scientific bodies, they are listed most readable first, and each one opens in a new tab. They are background for the whole entry rather than footnotes to individual sentences.

  1. Moisturizers StatPearls (NCBI Bookshelf) Reference text ncbi.nlm.nih.gov
  2. Atopic Dermatitis and the Stratum Corneum: Part 1: The Role of Filaggrin in the Stratum Corneum Barrier and Atopic Skin PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  3. Natural moisturizing factor as a biomarker for filaggrin PubMed Central Peer-reviewed, open access pmc.ncbi.nlm.nih.gov
  4. Caspase-14 is required for filaggrin degradation to natural moisturizing factors in the skin PubMed Peer-reviewed (abstract) pubmed.ncbi.nlm.nih.gov
  5. Loss-of-function mutations in the filaggrin gene lead to reduced level of natural moisturizing factor in the stratum corneum PubMed Peer-reviewed (abstract) pubmed.ncbi.nlm.nih.gov

SYNC does not publish medical advice. Nothing here replaces a consultation with a doctor or a pharmacist about your own skin.