What Is Peg-150 Stearate?
Peg-150 Stearate is a synthetic ingredient created by attaching roughly 150 units of ethylene oxide to stearic acid, a fatty acid that occurs naturally in plant and animal fats. The result is a large, water-loving molecule that also has an oil-compatible tail, making it an effective bridge between oil and water. Chemists began experimenting with these polyethylene glycol (PEG) derivatives in the mid-20th century as the beauty industry looked for gentler, more efficient ways to mix oily and watery ingredients. Peg-150 Stearate quickly found favor thanks to its reliable performance and mild skin feel.
Manufacturing starts with stearic acid, often sourced from coconut or palm oil. The acid is reacted with ethylene oxide under controlled heat and pressure, allowing the oxide units to attach in sequence. Producers stop the reaction once the average chain length reaches about 150 units, then purify the product to remove residues and by-products.
You will most often see Peg-150 Stearate in face washes, shower gels, shampoos, cream cleansers and some peel-off masks. Its ability to keep formulas stable while lifting away dirt and excess oil makes it a favorite in both budget and prestige lines.
Peg-150 Stearate’s Cosmetic Benefits/Uses
In skincare and haircare formulas Peg-150 Stearate serves one main purpose that delivers several user-friendly perks.
Cleansing: The ingredient reduces the surface tension of water, allowing cleansers to spread easily and surround oil, makeup and daily grime. This helps rinse impurities away without leaving a greasy film or stripping the skin’s natural moisture barrier.
Who Can Use Peg-150 Stearate
Because Peg-150 Stearate is considered mild and non-comedogenic, it generally suits all skin types including oily, combination, dry and sensitive. Its gentle cleansing action helps remove excess sebum without over-drying so even easily irritated skin usually tolerates it well. People with extremely dry or compromised skin may want to pair it with richer moisturizers since it offers little direct hydration.
Vegans and vegetarians should check product labeling or contact the manufacturer. Although stearic acid can be sourced from animal fat, most cosmetic suppliers now derive it from plant oils such as coconut or palm, making the final ingredient suitable for cruelty-free formulas.
No specific warnings exist for pregnant or breastfeeding women regarding topical use of Peg-150 Stearate. It is considered low risk because it stays on the skin’s surface and does not readily penetrate. That said, this is not medical advice and anyone who is pregnant or nursing should have a doctor review any product routine to be safe.
The ingredient does not heighten photosensitivity so it will not make skin more prone to sunburn. It is also fragrance-free and unlikely to interfere with actives like retinoids or vitamin C when used in the same routine.
Potential Side Effects/Adverse Reactions
Reactions to Peg-150 Stearate vary from person to person. The effects listed below are possible but uncommon when the ingredient is used correctly in a well-formulated product. Most people experience none of these issues.
- Mild stinging or redness on very sensitive skin
- Transient dryness if used in high-foaming cleansers without follow-up hydration
- Allergic contact dermatitis in individuals already allergic to polyethylene glycols
- Eye irritation if the product accidentally gets into the eyes
- Buildup and dullness on hair if not rinsed thoroughly in shampoos
If you notice any discomfort or persistent irritation stop use and consult a healthcare professional.
Comedogenic Rating
Rating: 1 / 5
Peg-150 Stearate is highly water soluble and used at low levels, so it rinses off the skin instead of sitting in pores where clogs start. Its large, bulky molecular size also makes it physically difficult to wedge into follicular openings. For these reasons it earns a near zero score, but since no ingredient is universally perfect it is given a cautious 1 rather than 0.
Suitable for people who are prone to acne or breakouts.
Residue can build up only if a cleanser is not rinsed thoroughly, so proper removal keeps any clogging risk negligible.
Summary
Peg-150 Stearate is a synthetic cleansing agent that acts as a bridge between water and oil, letting face washes, shampoos and body cleansers lift away sweat, sebum and makeup with ease. By reducing surface tension it helps formulas foam and spread evenly while maintaining a mild feel on skin and hair.
It is widely used in mass market and salon products because it is dependable, cost effective and easy to formulate with although it is not as famous as trendy actives like hyaluronic acid or niacinamide.
Safety data classify it as low risk, with irritation or allergy being rare and mostly limited to those already sensitive to PEGs. As with any new product it is wise to perform a quick patch test before adding it to your routine just to be safe.