Bouncy and Firm Sleeping Mask

The base most products are built on. It carries the other ingredients and has no safety concern.

A lightweight humectant and solvent similar in role to propylene glycol, used to carry actives and give lotions a lighter feel. CIR has reviewed it and considers it safe as used in cosmetics.

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

A silicone that gives a smooth, soft feel and helps hold water in the skin. Inert and well studied.

A glycol used very widely in Korean and Western skincare as a lightweight humectant, solvent, and gentle preservative-booster, often in place of traditional preservatives. It has a low reported irritation rate at use levels and is graded low concern in published assessments.

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 diester formed from malic acid and isostearyl alcohol. It conditions and smooths skin with no known safety issues in cosmetic use.

A blend of cetyl and stearyl fatty alcohols used to thicken lotions and soften skin. It is chemically unrelated to drying alcohols like ethanol, and the CIR expert panel has found fatty alcohols safe as used in cosmetics.

A saturated fatty acid found in palm oil and naturally in the skin, used as an emollient to soften and condition skin. It is one of the most studied fatty acids and is well tolerated.

A phospholipid emulsifier from soy or sunflower that binds water and oil and helps other ingredients absorb. It is a natural component of skin membranes, well tolerated, and reviewed as safe as used; a soy-derived grade is not a meaningful concern for a soy food allergy because the protein is largely absent.

A naturally occurring fatty acid (also made in the body and found in many foods) used to thicken lotions and help stabilize cleansing bars. It is one of the most well-studied emollient ingredients and is not a meaningful irritant at cosmetic use levels.

A synthetic conditioning agent derived from fatty acids. Used to soften and smooth skin and hair, it is well tolerated. Published safety data is limited outside industry cosmetic testing, but no concerns have been flagged in cosmetic registers.

A polyol (sugar alcohol) that attracts water to the skin. Like sorbitol and glycerin, it is well tolerated in skincare formulas. It is commonly used to boost hydration without the stickiness of other humectants.

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 synthetic polymer used to thicken and stabilize water-based formulas like gels and serums. It provides texture and suspension of particles without interfering with skin feel. Well established in cosmetics.

A natural, plant-based emulsifier made from cetyl alcohol and glucose that mixes oil and water phases in cosmetics. It is well studied, nonirritating in published testing, and presents no known safety concerns for cosmetic use.

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 chelating agent that binds trace metal ions to keep formulas stable and preservatives working properly. It is not a functional skincare "active" and only a very small amount is used, with minimal skin penetration expected.

A glycerin derivative used as a skin conditioner and preservative booster, often paired with phenoxyethanol to allow lower total preservative levels. It has a low irritation and sensitization profile in safety reviews.

A soothing, skin-conditioning compound (also found in comfrey root) commonly added to calm and hydrate irritated or sensitive skin. It has a long history of safe use with very low irritation potential.

A naturally occurring nucleoside used in anti-aging formulas, often marketed for smoothing the look of fine lines. It has a low irritation profile and no established hazard at cosmetic use levels.

An undisclosed scent blend that can contain dozens of components. The single most common cause of cosmetic contact allergy, and the blend is not itemized, so you cannot see what is in it.

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.

Carbomer is a synthetic polymer used purely to thicken and stabilize gels and lotions, with negligible skin penetration due to its large molecular size. Safety reviews have found low toxicity and minimal irritation potential even in leave-on use.

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 floral fragrance component and one of the EU-labelled fragrance allergens. Usually fine, worth watching if you react to scented products.

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 rose-scented fragrance ingredient found naturally in geranium and rose oil. It is one of the 26 fragrance allergens the EU requires to be labeled by name because a minority of people develop skin sensitization to it, though most users tolerate it without issue.

A floral, rose-like fragrance compound found in many essential oils. It is one of the 26 EU-designated fragrance allergens, meaning a documented minority of people can develop contact sensitization, so brands must disclose it above set thresholds.

Hydroxycitronellal is a lily-of-the-valley scented fragrance ingredient on the EU allergen disclosure list. It has well-documented sensitizing potential in patch-test studies, so it is worth checking the label if you have known fragrance sensitivities.

Benzyl salicylate is a fragrance fixative that also absorbs some UV light. It is on the EU allergen disclosure list, but the evidence suggests it sensitizes fewer people than most other listed fragrance allergens.

A humectant that holds water at the skin surface for a more hydrated look. No safety concern.

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

A broken-down form of hyaluronic acid with smaller molecules intended to penetrate more deeply into the skin. It functions as a humectant and is well tolerated, with the same safety profile as standard hyaluronic acid.

A chemically cross-linked form of sodium hyaluronate designed to remain on the skin surface longer and provide sustained hydration. It functions as a humectant and is well tolerated, with the same safety profile as standard hyaluronic acid.