Isostearyl Isostearate

Benefits
MoisturizingSoftening
Concerns
Malassezia Feeding

What is Isostearyl Isostearate?

Isostearyl isostearate is a synthetic ester formed from isostearyl alcohol and isostearic acid, both derived from branched-chain fatty acids typically sourced from vegetable oils. In cosmetics, it belongs to the emollient category, commonly found in lotions, creams, lipsticks, and hair care products. It works by mimicking natural skin lipids to reduce surface friction, providing a smooth, non-greasy feel while aiding in the even distribution of other ingredients. This ingredient improves formula stability and spreadability, helping products glide on effortlessly without a heavy residue. As a skin conditioning agent, it supports the skin's barrier by filling in rough patches and promoting a supple texture, making it suitable for anhydrous formulations like balms and sticks where cohesion and wear resistance are key.

Comedogenic Rating 4/5 Higher risk of clogging pores
EWG Safety Rating 1 View on EWG →
PubChem View on PubChem →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Binder
Helps hold solid ingredients together to form cohesive tablets, compacts, or sticks, improving pressability, integrity, and wear of the finished product.
Emollient
Softens and smooths skin by filling in surface roughness and improving slip; can also help reduce moisture loss when paired with occlusives and film formers.
Binding
Provides cohesion by helping ingredients stick together, improving the strength and integrity of pressed powders, tablets, or solid bars.
Skin conditioning agent
Maintains skin softness, smoothness, and flexibility.

Benefits

Provides moisturizing effects by helping retain skin hydration.

Softens and smooths skin texture for improved feel.

Enhances product slip and blendability as an emollient.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
Individuals with dry or rough skin seeking softness.
People with oily or acne-prone skin due to comedogenic potential.
People using anhydrous products like lip balms or sticks.
Individuals prone to malassezia-related issues like fungal acne.
Those preferring lightweight, non-greasy moisturizers.
Those sensitive to heavy emollients that may clog pores.

Safety Notes

  • Rated low hazard by EWG with scores of 1.
  • Generally recognized as safe for cosmetic use by regulatory reviews.

Frequently Asked Questions about Isostearyl Isostearate

What is isostearyl isostearate used for?

It serves as an emollient and binder in creams, lotions, and sticks to soften skin and improve product texture.

Is it safe for sensitive skin?

It has a low irritation profile and EWG score of 1, suitable for most but patch test recommended.

Does it clog pores?

It has a comedogenic rating of 4, so it may for oily skin but less issue for dry types.