C-Firma Fresh Day Serum

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

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.

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

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

A lightweight botanical oil from marula tree seeds, valued for softening and conditioning the skin. It is generally well tolerated across skin types.

A soothing plant extract traditionally used in skincare, valued for its potential anti-inflammatory properties. Published assessments note it is generally well tolerated in cosmetic formulations, though people with sensitivities to botanicals may want to patch test.

A plant-derived antioxidant found in seeds and grains, used in cosmetics to protect against free-radical damage. Published safety assessments grade it low-concern and it is generally well tolerated across skin types.

Green tea extract is a well-studied topical antioxidant with a long history of use in serums and moisturizers, generally well tolerated at cosmetic concentrations. Panel safety reviews of Camellia sinensis-derived ingredients have not identified meaningful topical hazard.

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.

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 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.

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

A water or bran extract of rice containing ferulic acid, small peptides and starches. It is a traditional East Asian skincare staple with some supporting antioxidant and mild-brightening data, but most of that evidence comes from cell or animal studies rather than large human trials, so the "brightening" claims on finished products go further than the direct evidence.

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 widely used, gentle preservative also common in food. It is generally well tolerated, though it can occasionally cause mild, transient irritation in people with already-compromised or very reactive skin.

A widely used preservative, safe at the legal limit of 1% or less. Often the "paraben-free" replacement.

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.

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 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.