Sodium Lactate

Sodium Lactate 

Sodium Lactate is the sodium salt of lactic acid and functions as a multifunctional cosmetic ingredient valued for its humectant, buffering, and formulation-support properties. It is typically produced through the neutralization of lactic acid, which is commonly derived via fermentation of plant-based sugars such as corn or beet sugar. The resulting material is a clear, water-soluble liquid that integrates easily into aqueous systems. The production process does not involve ethoxylation or petrochemical modification, supporting its use in clean and modern cosmetic formulations.

From a formulation standpoint, Sodium Lactate primarily enhances moisture retention by attracting and holding water within the skin and within the formulation itself. It also contributes to pH buffering and ionic strength, which can influence product stability and performance. In emulsions and surfactant systems, Sodium Lactate can improve skin feel, support barrier comfort, and enhance mildness. Its behavior is influenced by concentration, total water content, and interactions with other electrolytes or polymers in the system.

In finished products, Sodium Lactate contributes a hydrated, smooth skin feel without tackiness when used appropriately. At lower levels, it supports humectancy and skin comfort, while higher levels can noticeably boost hydration and slip. Because it is highly water soluble, Sodium Lactate is best suited for water-based and emulsified products such as lotions, creams, cleansers, toners, and liquid soaps.

From a clean standards and safety perspective, Sodium Lactate has a long history of safe cosmetic use and is widely accepted across global regulatory frameworks. It is biodegradable, non-volatile, and generally well tolerated in both rinse-off and leave-on applications. Clean positioning is supported by its bio-based origin and transparent manufacturing pathway, though formulation levels must be controlled to avoid potential stickiness or irritation in leave-on products.

Ingredient Identification

INCI Name: Sodium Lactate
CAS Number: 72-17-3

Physical & Technical Properties

Appearance: Clear to pale yellow liquid
Odor: Mild, characteristic
Solubility: Freely soluble in water
pH (10% solution): Approximately 6.5–7.5
Functional Role: Humectant, buffering agent, formulation aid

Typical Usage Levels (Skincare & Personal Care)

Lotions and Creams: 0.5–3.0%
Cleansers and Liquid Soaps: 1.0–5.0%
Toners and Aqueous Serums: 0.5–2.0%
Hair and Scalp Products: 0.5–2.0%

Actual usage levels may vary depending on desired hydration, product type, and overall electrolyte balance.

DIY Education and Formulation Guidance

For DIY formulators, Sodium Lactate is easy to work with and is added directly to the water phase or during cool-down with mixing. It is particularly useful in soap and cleanser formulations for improving mildness and skin feel. Because Sodium Lactate contributes electrolytes, excessive use may thin emulsions or reduce viscosity in polymer-thickened systems, so incremental adjustments are recommended.

Sodium Lactate should not be confused with lactic acid, as it does not provide exfoliating alpha-hydroxy acid activity at cosmetic pH levels.

Formulation Compatibility & Common Combinations

Sodium Lactate is compatible with most humectants such as glycerin, propanediol, and sorbitol. It works well alongside emulsifiers, surfactants, and mild preservation systems. In electrolyte-sensitive systems, compatibility testing is recommended to ensure viscosity and stability are maintained.

Shelf Life, Storage, and Packaging

Shelf Life: Typically 24 months under recommended storage conditions
Storage Conditions: Store in a cool, dry environment away from direct heat
Packaging Recommendations: HDPE or PET bottles with tight closures
Handling Notes: Hygroscopic material; keep containers sealed to prevent moisture imbalance

Regulatory & Safety Notes

Regulatory Status: Approved for cosmetic use globally, including the United States and European Union
California Proposition 65: Not listed
EWG Context: Generally categorized as low hazard based on available data
Irritation and Sensitization: Generally well tolerated when used at appropriate cosmetic concentrations
Clean Beauty Compatibility: Bio-based, biodegradable, and compatible with clean, minimalist, and transparency-focused formulation standards