Ingredient review

Sodium Myristyl Aspartate

INCI: Sodium Myristyl Aspartate

A mild, amino-acid-based surfactant that cleanses without stripping the skin, making it a good choice for sensitive or dry skin types.

beautyskincarecleansing agent

In plain English

Sodium Myristyl Aspartate is a gentle cleansing ingredient made from aspartic acid (an amino acid) and myristyl alcohol (a fatty alcohol). It helps remove dirt, oil, and makeup from your skin without being harsh or drying. Because it's derived from amino acids, it's often used in 'gentle' or 'sulfate-free' cleansers. It also helps blend oil and water together in a formula, so the product stays smooth and effective.

Review score

Safety, usefulness, and evidence

4.0Good

4.0/ 5

Potentially useful with some tradeoffs

The evidence base is useful, but some claims depend heavily on the formula.

Risk flags are low for most users, though the finished product can still irritate.

Source: semi synthetic
Evidence: moderate
Irritation: low
Clogging risk: low

How reviews are scored

Quick decision guide

Useful, but context matters

Sodium Myristyl Aspartate is generally a lower-concern ingredient when the full formula suits your skin.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

Step 1Start with the score, then check the irritation and clogging risk before judging Sodium Myristyl Aspartate.
Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

Sodium Myristyl Aspartate is a semi-synthetic surfactant and emulsifier. It is the sodium salt of the ester formed from aspartic acid and myristyl alcohol. It belongs to the family of amino-acid-based surfactants, known for their mildness and skin compatibility.

How it works

In a cosmetic product, Sodium Myristyl Aspartate works by reducing the surface tension between water and oil, allowing them to mix and rinse away impurities. Its aspartic acid portion is attracted to water, while the myristyl chain is attracted to oil and dirt. This dual action helps lift grime from the skin while leaving the skin's natural moisture barrier relatively intact.

Pros

Mild on skin

Because it's derived from an amino acid, it cleanses without stripping the skin's natural oils, reducing the risk of dryness or irritation.

Sulfate-free alternative

It provides effective cleansing without using harsh sulfates like SLS or SLES, making it a popular choice for gentle and sensitive-skin formulas.

Cons and cautions

Lower foam volume

Compared to traditional sulfate cleansers, it produces less foam, which may feel less satisfying to people who associate lather with cleanliness.

Higher cost

Amino-acid-based surfactants are generally more expensive to produce, which can increase the price of the final product.

Best for

People with dry or sensitive skin looking for a mild cleanser
Anyone seeking a sulfate-free or amino-acid-based cleansing routine

Use caution if

Those who prefer high-foaming, bubbly cleansers may find this too low-lather

Usage tips

Use in a rinse-off cleanser for best results; it is not typically used in leave-on products.

Pair with other mild surfactants like Cocamidopropyl Betaine to boost foam without increasing irritation.

Safety summary

Sodium Myristyl Aspartate is considered safe for use in cosmetics. It has low irritation and comedogenic potential, making it suitable for most skin types, including sensitive skin. No significant safety concerns have been reported in the scientific literature.

Research notes

Amino-acid-based surfactants like Sodium Myristyl Aspartate have been studied for their mildness and skin compatibility. Research indicates they cause less protein denaturation and lipid extraction compared to traditional anionic surfactants, supporting their use in gentle cleansers.

Common label clues

Typical concentration: 1–5% in rinse-off products
Regulatory status: Approved for use in cosmetics by the FDA and the European Commission. No known restrictions at typical use levels.
Common uses: Cleansers, Facial washes, Shampoos, Body washes
Environmental note: As an amino-acid-based surfactant, it is generally considered biodegradable and less harmful to aquatic life compared to some conventional surfactants.

Good to know

Sodium Myristyl Aspartate is often found in 'gentle' or 'hydrating' cleansers marketed for sensitive skin.
It is biodegradable and considered more environmentally friendly than some traditional surfactants.

Common questions

What is Sodium Myristyl Aspartate in beauty products?

What does Sodium Myristyl Aspartate do in a beauty product?

Is Sodium Myristyl Aspartate safe for most people?

Who should be careful with Sodium Myristyl Aspartate?

Those who prefer high-foaming, bubbly cleansers may find this too low-lather

Research sources

CosIng - European Commission databaseOpen PubMed - Amino acid surfactants reviewOpen Environmental Working Group (EWG) Skin DeepOpen

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.