Ceramide Barrier Serum (Travel Size)

A plant-derived water or extract used mainly as a soothing humectant filler. Evidence for dramatic skin benefits beyond mild hydration and soothing is limited, but it is well tolerated by most people.

A corn-derived solvent and humectant that has largely replaced propylene glycol in "clean" formulas; CIR reviewed the alkane diol group and found use concentrations up to about 40 percent in leave-on products like deodorant sticks with no meaningful irritation signal.

A stable, saturated version of squalene, a lipid the skin already produces, now usually sourced from olives or sugarcane instead of shark liver. It is very well tolerated across skin types and helps reinforce the skin barrier.

A humectant that draws water into the skin. One of the best-studied, best-tolerated ingredients in personal care.

Gluconolactone is a polyhydroxy acid that exfoliates gently while also acting as a humectant and mild antioxidant, and it is generally recommended for sensitive or barrier-compromised skin over smaller AHAs. A full cosmetic panel review found it safe as used, though some users still report mild stinging or redness at higher concentrations.

A polysaccharide produced by fermentation of fungal cultures, used to thicken and stabilize formulas. It is well tolerated in cosmetics and often chosen by natural-leaning brands. It functions similarly to other gelling agents but comes from a more controlled fermentation source.

The sodium salt of benzoic acid, used as a preservative in both foods and cosmetics. Decades of safety review support its use at typical cosmetic concentrations, with mild irritation the main reported issue in sensitive skin.

Xanthan gum is a microbial-fermentation-derived polysaccharide used to thicken and stabilize textures, similarly common in food. Cosmetic panel review of this and related microbial gums found them safe as used, with no meaningful irritation signal at typical concentrations.

A PEG-type emulsifier (ethoxylated cetearyl alcohol) that helps blend the water and oil parts of a cream. CIR concluded ceteareth ingredients are safe as used, with the one caveat that they are not meant for broken or damaged skin.

A polysaccharide extracted from yeast cell walls or oat bran. Used for hydration and skin conditioning, beta-glucan is well tolerated with emerging evidence for supporting skin barrier function. No safety concerns flagged in cosmetic use.

An antioxidant that helps protect a formula and condition skin. Well tolerated.

A fatty alcohol used to soften skin and stabilize creams. Despite the name, it does not dry the skin.

Caprylyl glycol is a plant-derived humectant that also has mild antimicrobial properties, so it is commonly paired with other preservatives to allow lower overall preservative levels. Available data do not point to meaningful irritation or sensitization concerns at typical use levels.

A linoleic-acid-rich plant oil used as an emollient and, in some small pediatric studies, associated with support of the skin barrier when applied to infant skin. It is well tolerated with a low reported rate of contact reactions.

A mineral thickener and anti-caking agent widely used in sunscreens and cosmetics to control texture and prevent ingredient separation. CIR has reviewed silica in cosmetic use and found no basis for concern at the levels used topically.

A waxy sterol found naturally in skin and used in cosmetics as an emollient and emulsifier. It supports the skin barrier and is well tolerated across skin types.

A lab-made version of a lipid naturally found in the outer skin barrier. It is added to creams and cleansers to help replace lipids that washing can strip away, and it is not linked to irritation or safety concerns.

One of the three major ceramides naturally found in human skin. Ceramide AP plays a critical role in maintaining the skin barrier and is extensively studied as a safe, essential ingredient. It is derived synthetically or from plant sources.

A larger, gentler alpha hydroxy acid than glycolic acid, used to exfoliate and to draw in moisture. It can still cause stinging or increased sun sensitivity at higher concentrations, so daytime SPF use is sensible, but it is generally better tolerated than glycolic acid.