Madeca Vitamin 15+ Glowing Serum

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

A form of vitamin B3 used to support a more even-looking tone and a comfortable barrier. Well tolerated at cosmetic levels.

A stable vitamin C derivative used to brighten and provide antioxidant support, more shelf-stable than pure ascorbic acid. It is generally well tolerated, though strong vitamin C forms can sting sensitive skin.

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 fast-evaporating solvent used to carry actives and give toners a light, "clean" feel; at the concentrations used in classic astringents it can be genuinely drying or irritating with repeated use, especially on dry or compromised skin, though it is not inherently toxic and is a normal, well-studied cosmetic ingredient.

A gentle, stable vitamin C derivative that the skin converts to active vitamin C, popular for brightening with less irritation than pure ascorbic acid. It is well tolerated and graded low concern in published assessments.

A water-soluble humectant that holds moisture and gives essences a soft feel. It is well tolerated and graded low concern in published assessments.

Pentylene glycol is a humectant and solvent that also offers mild antimicrobial support in formulas. It is generally well tolerated, with only rare reports of irritation, mostly in already sensitive or compromised skin.

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

A small glycol used as a solvent and to boost the absorption of actives, and to help preservatives work at lower levels. It is well tolerated and graded low concern in published assessments.

A lightweight, odorless emollient made by combining coconut or palm-derived fatty acids with glycerin. It spreads easily, feels non-greasy, and has a long history of use in skin and hair products with no meaningful irritation or sensitization signal.

This branched ester is a CIR-reviewed emollient used to give creams and lotions a silky, fast-absorbing after-feel. It is generally rated non-comedogenic and has not shown irritation or sensitization concerns in the available safety data.

A buffering agent used in tiny amounts to set a product's pH, most often alongside gel-forming polymers. It is graded low concern in published assessments at the levels used.

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 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 soothing humectant that helps skin and hair look conditioned. Very well tolerated.

A light, low-odor glycol used as a solvent and humectant, extremely common in Korean toners and essences. It has a low reported irritation rate and is graded low concern in published assessments.

A plant-derived emollient oil rich in ricinoleic acid, used in skincare for decades. Contact allergy has been reported but is uncommon relative to how widely it is used in leave-on products.

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

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.

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 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 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 more stable, esterified form of vitamin E used as an antioxidant and skin-conditioning ingredient. It is a different substance from the vitamin E acetate implicated in vaping-related lung injury, which involved inhaling the oil, not applying it topically to skin.

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

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.

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 beta hydroxy acid used to smooth texture and clear pores. Safe at cosmetic levels; can be mildly irritating if overused.

The most well-studied form of topical vitamin C, used as an antioxidant and to support collagen signaling and brighten uneven tone. It is acidic and can sting or irritate sensitive skin, and it oxidizes readily once a bottle is opened, which can reduce its effectiveness rather than create a safety issue.