Ingredient review

Sodium Myristyl Sulfate

INCI: Sodium Myristyl Sulfate

An effective but potentially drying cleanser that may irritate sensitive skin, especially in high concentrations.

beautyskincarecleansing

In plain English

Sodium Myristyl Sulfate is a surfactant, which means it helps water mix with oil and dirt so they can be rinsed away. It creates a rich lather in soaps and shampoos, but it can strip the skin of its natural oils, leading to dryness or irritation for some people.

Review score

Safety, usefulness, and evidence

3.5Good
3.5/ 5

Potentially useful with some tradeoffs

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

Main practical flags: irritation is moderate; clogging risk is low.

Source
synthetic
Evidence
moderate
Irritation
moderate
Clogging risk
low
How reviews are scored

Quick decision guide

Useful, but context matters

Sodium Myristyl Sulfate can be useful, but watch for some irritation potential.

Plain-English read

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

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Sodium Myristyl Sulfate.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. 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

moderate

Can bother some users, especially with frequent use, damaged skin, or strong companion ingredients.

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 Sulfate is a synthetic surfactant derived from myristyl alcohol, a fatty alcohol often sourced from coconut or palm oil. It belongs to the alkyl sulfate family, similar to Sodium Lauryl Sulfate (SLS), but is generally considered slightly milder.

How it works

In a cosmetic product, Sodium Myristyl Sulfate lowers the surface tension of water, allowing it to penetrate oils and dirt on the skin or hair. This action helps lift away impurities, which are then suspended in the foam and rinsed off, leaving the surface clean.

Pros

Strong cleanser

Effectively removes excess oil, sweat, and impurities, leaving skin feeling thoroughly clean.

Good lather

Produces a rich foam that many people associate with a satisfying cleansing experience.

Cons and cautions

Can be drying

May strip the skin's natural moisture barrier, leading to tightness, flakiness, or increased sensitivity over time.

Potential irritant

For those with sensitive skin or conditions like rosacea, it can cause redness, stinging, or irritation.

Best for

  • People with normal to oily skin looking for a deep cleanse
  • Those who prefer a foamy lather in their cleansers

Use caution if

  • Individuals with dry, sensitive, or eczema-prone skin
  • Anyone with a compromised skin barrier or active irritation

Usage tips

Use only on wet skin and rinse thoroughly to minimize residue.
Follow with a moisturizer to replenish hydration after cleansing.
If you have sensitive skin, look for products where this ingredient appears low on the ingredient list.

Safety summary

Sodium Myristyl Sulfate is considered safe for use in rinse-off cosmetics at typical concentrations. However, it can be drying and irritating for some skin types, especially with prolonged or frequent use.

Research notes

Studies indicate that alkyl sulfates like Sodium Myristyl Sulfate can disrupt the skin barrier and increase transepidermal water loss (TEWL), but they are less irritating than Sodium Lauryl Sulfate in some tests.

Common label clues

Typical concentration
1% to 10% in rinse-off products
Regulatory status
Approved for use in cosmetics by the FDA and the European Commission, with no specific concentration restrictions for rinse-off products.
Common uses
Shampoos, Body washes, Facial cleansers, Bar soaps
Environmental note
Sodium Myristyl Sulfate is generally biodegradable, but its production may involve palm oil, which can contribute to deforestation if not sustainably sourced.

Good to know

  • Sodium Myristyl Sulfate is often used in combination with milder surfactants to balance cleansing power and gentleness.
  • It is not the same as Sodium Laureth Sulfate (SLES), which is typically less irritating due to its ethoxylation.

Common questions

What is Sodium Myristyl Sulfate in beauty products?

Sodium Myristyl Sulfate is a surfactant, which means it helps water mix with oil and dirt so they can be rinsed away. It creates a rich lather in soaps and shampoos, but it can strip the skin of its natural oils, leading to dryness or irritation for some people.

What does Sodium Myristyl Sulfate do in a beauty product?

In a cosmetic product, Sodium Myristyl Sulfate lowers the surface tension of water, allowing it to penetrate oils and dirt on the skin or hair. This action helps lift away impurities, which are then suspended in the foam and rinsed off, leaving the surface clean.

Is Sodium Myristyl Sulfate safe for most people?

Sodium Myristyl Sulfate is considered safe for use in rinse-off cosmetics at typical concentrations. However, it can be drying and irritating for some skin types, especially with prolonged or frequent use.

Who should be careful with Sodium Myristyl Sulfate?

Individuals with dry, sensitive, or eczema-prone skin Anyone with a compromised skin barrier or active irritation

Research sources

Cosmetic Ingredient Review (CIR) - Safety Assessment of Alkyl SulfatesOpenPubMed - Surfactant irritation potentialOpenEuropean Commission CosIng DatabaseOpen

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.