Beauty ingredients explained in plain English

MDM Hydantoin is an effective preservative but may irritate sensitive skin due to its slow release of formaldehyde.

A synthetic preservative that helps keep products fresh but may cause irritation in sensitive skin.

MEA-Benzoate is a synthetic preservative helper that extends shelf life but may cause irritation for sensitive skin.

A synthetic preservative with limited public research; generally considered safe at low concentrations but may cause irritation in sensitive individuals.

Methenamine is a synthetic preservative that works by slowly releasing formaldehyde, which can be effective but raises concerns for skin sensitivity and long-term safety.

Methenammonium Chloride is a synthetic preservative that helps keep products fresh but may cause irritation in sensitive skin.

A synthetic solvent and preservative that helps products stay fresh but may cause irritation for sensitive skin.

Methyl 2,6-dihydroxybenzoate is a synthetic fragrance and preservative helper that can be irritating for sensitive skin.

A synthetic preservative helper that keeps products fresh and stable, but it's not a star active ingredient for your skin.

A gentle preservative booster and fragrance component that helps keep products fresh, but may cause mild irritation in very sensitive skin.

A powerful preservative that is a common contact allergen; best avoided by those with sensitive skin.

Methylene glycol is a controversial preservative that releases formaldehyde; it is effective but can cause irritation and is best avoided by sensitive individuals.

A powerful but controversial preservative that is a common allergen; many prefer to avoid it.

Methylparaben is an effective, low-irritation preservative, but some consumers avoid it due to concerns about endocrine disruption.

An effective preservative and antistatic agent, but can be irritating to sensitive skin or eyes at higher concentrations.

An effective preservative but can be irritating for sensitive skin at higher concentrations.

Natamycin is a gentle, naturally derived preservative that fights fungi and yeast, making it a good option for sensitive skin formulas.

Nisin is a gentle, naturally derived preservative that helps keep skincare products fresh while supporting a healthy skin microbiome.

A gentle synthetic preservative that helps keep your skincare products fresh and safe without common irritation.

O-Tolyl Biguanide is an effective preservative but may cause skin irritation in sensitive individuals.

Octylisothiazolinone is an effective preservative but can be a skin sensitizer, so it's mainly restricted to rinse-off formulas.

Ortho-phenylphenol is a synthetic preservative that is effective but carries moderate irritation and regulatory restrictions, especially for leave-on products.

Oxyquinoline is an effective preservative but may cause skin irritation in sensitive individuals; its use is restricted in some regions.

Oxyquinoline benzoate is a synthetic preservative that helps keep products fresh, but it may cause skin irritation in sensitive individuals and is less common in modern formulations.

Oxyquinoline Sulfate is a synthetic preservative that helps keep products fresh, but it can be irritating for sensitive skin and is less common in modern formulations.

p-Anisic acid is a mild, naturally derived preservative helper that also offers gentle antioxidant and soothing benefits, making it a safe choice for most skin types.

P-Cresol is a synthetic fragrance and preservative compound that can be irritating; it is rarely used in modern leave-on skincare and is best avoided by sensitive skin.

p-Isopropylphenol is a synthetic preservative that helps keep products fresh, but it may cause irritation for sensitive skin types.

Parabens are effective, low-irritation preservatives, but consumer concerns about potential endocrine disruption have led many brands to seek alternatives.

Parabens are effective preservatives with a long safety record, but concerns about hormone disruption have led many to seek paraben-free alternatives.

A synthetic preservative booster that helps prevent microbial growth but may cause irritation for sensitive skin.

A paraben-based preservative that is effective but controversial due to paraben safety concerns.

Phenoxyacetic acid is a synthetic ingredient used to boost preservative systems and adjust pH, but it is less common than alternatives like phenoxyethanol.

Phenoxyethanol is a safe and effective preservative that keeps your products fresh and free from harmful bacteria.

Phenoxyethylparaben is a paraben preservative that is rarely used today because of consumer concerns and regulatory restrictions in some regions.

Phenoxyisopropanol is a less common synthetic preservative that helps keep products fresh, but it has limited safety data compared to alternatives like phenoxyethanol.

A gentle preservative booster and humectant that helps keep formulas fresh and hydrated without common irritation.

A synthetic enzyme blocker that helps preserve active ingredients but may cause irritation at higher concentrations.

Phenylparaben is a synthetic preservative that is effective but controversial due to potential endocrine-disrupting concerns; it is now rarely used in modern skincare.

Phenylpentanol is a gentle synthetic ingredient that helps preserve products and lightly conditions skin, making it a safer alternative to harsher preservatives.

Phthalates are controversial synthetic chemicals linked to endocrine disruption; most are banned or restricted in cosmetics in many regions, but consumers should still check labels for hidden sources.

An effective, low-irritation preservative that helps keep your products safe from germs, but has faced some regulatory scrutiny in Europe.

A gentle, naturally-derived preservative booster that helps keep your skincare products fresh without harsh chemicals.

A gentle, fermentation-derived preservative booster that helps keep products fresh without harsh chemicals.

A synthetic preservative booster that helps keep products fresh, but may cause irritation for sensitive skin.

Potassium Acetate is a safe, low-irritation salt that helps control a product's pH and can support preservative systems.

A gentle, widely used preservative that helps keep your products safe from bacteria and mold without common irritation.

Potassium borate is a synthetic salt used to adjust pH and preserve products, but it raises safety concerns due to its boron content and potential for irritation.

Potassium bromide is a synthetic salt used as a preservative, but it has limited cosmetic use and potential irritation concerns.

A paraben preservative that is effective but controversial due to potential endocrine concerns; many brands now avoid it.

A paraben preservative that is effective against microbes but has raised some safety concerns in certain consumer circles.

Potassium iodide is a safe preservative helper in tiny amounts, but it is not a skin-beneficial active and may be unnecessary in well-formulated products.

Potassium Metabisulfite is an effective preservative but can be a common allergen, especially for those with sulfite sensitivity.

A widely used preservative that prevents microbial growth, but has raised some safety concerns regarding potential endocrine disruption.

A synthetic preservative that helps keep products fresh but may cause irritation for sensitive skin at higher concentrations.

A mild, well-tolerated preservative that helps keep your skincare products fresh and safe from spoilage.

Potassium Paraben is an effective preservative but has raised concerns about potential endocrine disruption, leading many brands to phase it out.

Potassium Phenoxide is a synthetic preservative booster that helps keep products fresh, but may cause irritation in sensitive individuals at higher concentrations.

Potassium Propionate is a mild preservative that helps keep products fresh and stable, but it is not as widely studied as some alternatives.

Potassium propylparaben is an effective preservative but has raised concerns about potential endocrine disruption, leading many brands to phase it out.