Distearyl Peg-18 Formoyl Glutamate: What Is It, Cosmetic Uses, Benefits & Side Effects

Curious about this ingredient? In this article we're explaining exactly what it is and why it's used within cosmetic formulations.
Updated on: June 27, 2025
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We verify all information on this page using publicly available nomenclature standards from The Personal Care Products Council (PCPC), the European Commission's CosIng database and documentation provided directly by ingredient manufacturers. Our analysis is based on technical data from these sources to ensure accuracy and reliability.

What Is Distearyl Peg-18 Formoyl Glutamate?

Distearyl PEG-18 Formoyl Glutamate is a skin-loving ingredient created by linking stearyl alcohol, polyethylene glycol with an average chain length of 18 units, and a derivative of the amino acid glutamic acid. The result is a waxy, partly water-soluble compound that can easily mingle with both oils and water in a formula. It traces its roots to the search for gentle plant and amino acid based moisturizers in the late twentieth century, when chemists began experimenting with fatty alcohols and amino acids to improve skin feel without heavy oils. Production starts with stearyl alcohol usually sourced from vegetable fats like coconut or palm. This fatty alcohol is reacted with ethylene oxide to form PEG-18 stearyl ether, which is then combined with formylated glutamic acid to create the final molecule. Thanks to its dual love for water and oil, it acts as a softening agent in many personal care items. You will most often spot it in facial and body moisturizers, lightweight lotions, nourishing masks, leave-on serums, anti-aging creams, and sometimes in hair conditioners where extra smoothness is desired.

Distearyl Peg-18 Formoyl Glutamate’s Cosmetic Benefits/Uses

This ingredient is valued mainly for one key role in skin care formulations.

As a skin conditioning agent it helps bind moisture to the surface of the skin, leaving it feeling softer and smoother. Its fatty alcohol portion forms a thin protective film that limits water loss while the PEG and glutamate parts draw in hydration, creating a comfortable non-greasy finish.

Who Can Use Distearyl Peg-18 Formoyl Glutamate

This ingredient plays well with most skin types. Its light non greasy finish makes it helpful for dry or normal skin that needs extra softness while its low weight texture means oily or combination skin can usually tolerate it without feeling heavy. Sensitive skin tends to accept it because it is mild and free of common irritants, though people with a history of reactions to fatty alcohols should still stay alert.

The stearyl alcohol portion is typically sourced from vegetable fats and the rest of the molecule is made in a lab, so products that use only plant based sources can fit into vegan and vegetarian routines. As with any finished cosmetic, cruelty free status depends on the brand’s overall policy not the ingredient itself.

No data links Distearyl Peg-18 Formoyl Glutamate to problems during pregnancy or while nursing. It is widely used in everyday moisturizers and considered low risk when applied on intact skin. This is not medical advice and anyone who is pregnant or breastfeeding should have a quick chat with a doctor before adding new products, just to be safe.

The molecule does not absorb UV light or make skin more prone to sunburn, so it is not classed as photosensitizing. It can be used morning or night without extra sun precautions beyond the usual daily sunscreen.

Because it helps formulas glide, you might also find it in eye creams or lip balms. If it slips into the eyes it can sting mildly so rinse with water if that happens.

Potential Side Effects/Adverse Reactions

Reactions to topical Distearyl Peg-18 Formoyl Glutamate differ from person to person. The points below list potential side effects yet most people will not notice any problems when the ingredient is used at the levels approved for cosmetics.

  • Transient redness or warmth on very reactive skin
  • Mild stinging if applied to cracked or freshly exfoliated skin
  • Allergic contact dermatitis in individuals sensitive to fatty alcohols or PEG compounds
  • Temporary eye irritation if product migrates into the eye area
  • Rare clogging of pores in users extremely prone to comedones

If any of these effects occur discontinue use and seek medical advice if symptoms persist or worsen.

Comedogenic Rating

Rating: 1 / 5

Distearyl PEG-18 Formoyl Glutamate carries a low comedogenic risk because its main building blocks are a highly purified fatty alcohol and water-attracting PEG units that tend to rinse cleanly from pores. While stearyl alcohol alone can score around 2, the addition of the PEG chain increases solubility and reduces the likelihood of buildup, nudging the overall rating down to 1.

Most people prone to acne or breakouts can use products containing this ingredient without noticing extra clogged pores.

Formulation level and the full product matrix still matter; very occlusive creams loaded with oils could override the low rating of a single component.

Summary

Distearyl PEG-18 Formoyl Glutamate is chiefly a skin conditioning agent that softens and smooths by forming a light protective film while its PEG and glutamate segments draw in water. This dual action boosts moisture retention so skin feels supple yet never greasy.

It shows up in a modest range of moisturizers, lotions and masks but is not as ubiquitous as classics like glycerin or hyaluronic acid. Brands that like plant-derived, amino acid inspired ingredients use it to give products a silky finish without heaviness.

Current safety data classify it as low risk for irritation or sensitization at normal cosmetic levels. Even so it is wise to patch test any new product to be certain your skin agrees with the full formula.

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