What Is Peg-120 Distearate?
Peg-120 Distearate is a large molecule made by attaching about 120 units of ethylene oxide to distearic acid, a fatty acid that comes from plant or animal fats. The result is a waxy solid that mixes well with both water and oil, a handy trait in personal care formulas. Chemists began experimenting with polyethylene glycol (PEG) based ingredients in the mid-20th century to improve the feel and stability of soaps and creams, and Peg-120 Distearate grew popular as gentler cleansers replaced traditional bar soap in the 1970s and 1980s.
Production starts with stearic acid that is first converted to distearate, then reacted with ethylene oxide under heat and pressure. Careful control of the reaction gives an average chain length of 120 ethylene oxide units, which balances thickening power with mildness. After purification and drying the ingredient is shipped as flakes or pellets that melt easily into formulations.
You will most often find Peg-120 Distearate in face and body washes, micellar waters, shampoos, shower gels, exfoliating scrubs, clay or cream masks, makeup removers and some lightweight moisturizers where a silky rinse-off feel is desired.
Peg-120 Distearate’s Cosmetic Benefits/Uses
This ingredient plays two main roles that improve the performance and pleasure of many rinse-off products.
- Cleansing: Peg-120 Distearate helps loosen dirt, oil and makeup so they can be rinsed away without stripping the skin or hair. Its large size and fatty backbone make it milder than stronger surfactants, which is why it often shows up in formulas aimed at sensitive skin.
- Emulsifying: It holds oil and water together, keeping a formula smooth and preventing separation on the shelf as well as during use. Stable emulsions spread evenly, feel silky and rinse off cleanly.
Who Can Use Peg-120 Distearate
Peg-120 Distearate is considered gentle enough for most skin types, including dry, normal, combination and oily skin. Its mild cleansing action makes it especially appealing for sensitive skin that cannot tolerate stronger surfactants, though anyone with a known polyethylene glycol allergy should avoid it.
The ingredient itself can be sourced from either plant or animal fats. Many large suppliers use vegetable-derived stearic acid, yet this is not guaranteed. Strict vegans and vegetarians should look for brands that confirm a plant origin or carry a third-party vegan certification.
Current safety data show no specific risks for people who are pregnant or breastfeeding when Peg-120 Distearate is used in rinse-off or leave-on cosmetics. This is not medical advice and anyone expecting or nursing should review their skincare routine with a healthcare professional.
Peg-120 Distearate does not make skin more sensitive to sunlight, so there is no extra need for daytime sun protection beyond normal best practice.
Potential Side Effects/Adverse Reactions
Responses to any cosmetic ingredient differ from person to person. The effects listed below are possible yet uncommon when Peg-120 Distearate is incorporated at typical use levels by reputable manufacturers.
- Mild skin irritation
- Temporary redness or stinging on very sensitive skin
- Allergic contact dermatitis in individuals allergic to polyethylene glycols
- Eye irritation if a product is accidentally rubbed into the eyes
- Follicular clogging in acne-prone users when the overall formula is rich or heavy
If any discomfort, redness or swelling develops after applying a product containing Peg-120 Distearate discontinue use and consult a healthcare professional.
Comedogenic Rating
Rating: 1/5
Peg-120 Distearate earns a low score because its large PEG chain keeps it mostly water soluble, so it rinses away rather than lingering in pores. It is also used at modest percentages and paired with other mild surfactants, further reducing any clogging risk. Only when blended into very rich or occlusive formulas could it contribute to buildup.
Most people prone to acne can use products with Peg-120 Distearate without extra worry, though individual reactions always vary.
Keep in mind that an entire formula’s thickness, the presence of heavy oils and personal skin chemistry play a bigger role in breakouts than this single ingredient.
Summary
Peg-120 Distearate works as a cleanser and emulsifier. Its fatty core grabs onto oils and dirt while its long PEG chain loves water, so it bridges the two phases and lets grime wash away easily. The same dual nature keeps oil-water mixes stable on the shelf, giving creams and gels a smooth, silky glide.
It shows up in many modern face washes, shampoos and micellar waters but is not as famous as headline surfactants like SLS or cocamidopropyl betaine. Formulators reach for it when they need mildness, thickness and a clean rinse all at once.
Current research supports Peg-120 Distearate as safe in both rinse-off and leave-on products with only rare reports of irritation or allergy. Still, skin is personal so it is smart to patch test any new product that lists this ingredient before fully adding it to your routine.