Beauty ingredients explained in plain English

A fragrant, soothing oil with antioxidant benefits, but can be irritating for sensitive skin due to its natural fragrance compounds.

Rose flower oil adds a luxurious scent and offers mild antioxidant and soothing benefits, but it can cause irritation in sensitive individuals and is primarily used for fragrance.

Rose geranium oil adds a pleasant floral scent and may help balance oily or combination skin, but it can be irritating for sensitive skin if used undiluted.

Rose Ketone-2 is a synthetic fragrance compound that adds a soft, powdery rose note to products, but it offers no skincare benefits and may be a concern for those with fragrance sensitivities.

Rose Ketone-3 is a synthetic fragrance ingredient that gives a pleasant rose scent, but may cause irritation in sensitive individuals.

Rose Ketone-4 is a natural fragrance compound that gives a rose-like scent, but it can be a skin sensitizer for some people.

Rose Ketone-5 adds a pleasant rose scent but can be a skin sensitizer for some, especially those with fragrance allergies.

Rosemary Flower Oil offers antioxidant and antimicrobial benefits but can be irritating for sensitive skin due to its essential oil nature.

Rosemary leaf oil adds a pleasant herbal scent and antioxidant benefits, but can be irritating for sensitive skin if used at high concentrations.

Rue Herb Oil is a fragrant essential oil with limited skincare benefits and significant safety concerns, including phototoxicity and skin irritation, making it a risky choice for most everyday routines.

A fragrant botanical oil with traditional uses, but limited modern research on its specific skincare benefits and a moderate risk of skin irritation.

A fragrant essential oil from fir needles that adds a forest-like scent to products, but may irritate sensitive skin due to its aromatic compounds.

Salicylaldehyde is a fragrant compound with mild antimicrobial properties, but it can be a skin sensitizer for some people.

Sandalwood oil is a gentle, aromatic oil that may help calm skin and provide a pleasant scent, but it is primarily used for fragrance.

Santalol is a gentle, naturally derived fragrance and soothing ingredient from sandalwood, but its benefits are mostly aromatic rather than therapeutic.

Santalyl Acetate is a synthetic fragrance ingredient that adds a sandalwood-like scent to products; it is generally considered safe at low concentrations but offers no direct skincare benefits.

Sassafras Root Oil is a fragrant essential oil that is largely avoided in modern skincare due to safety concerns over its main component, safrole, which is regulated as a potential carcinogen.

Satsuma Flower Oil adds a fresh citrus scent and mild astringent feel, but its fragrance components can be irritating for sensitive skin.

A fragrant citrus oil that can brighten the complexion but may cause irritation in sensitive skin due to natural limonene content.

Satsuma Peel Oil adds a fresh citrus scent and mild antioxidant benefits, but its fragrance components can irritate sensitive skin.

A synthetic fragrance ingredient with limited safety data; best used in low concentrations and may cause irritation in sensitive individuals.

A natural essential oil that adds a fresh pine scent to products but may cause irritation in sensitive skin.

Siberian Fir Needle Oil adds a fresh, woodsy scent to products but can be irritating for sensitive skin, especially at higher concentrations.

Siberian Fir Oil adds a fresh, pine-like scent to products but can be irritating for sensitive skin, especially at high concentrations.

Silver Fir Leaf Oil adds a fresh, forest-like scent to products but can be irritating for sensitive skin, especially at higher concentrations.

Silver fir needle oil adds a fresh, woodsy scent to products but may irritate sensitive skin and lacks strong evidence for skincare benefits beyond fragrance.

Silver Fir Oil adds a fresh, forest-like scent to products but can be irritating for sensitive skin and is mainly used for fragrance rather than active skincare benefits.

Silver Fir Wood Oil adds a fresh, forest-like scent to products but may irritate sensitive skin due to its essential oil components.

Siparuna Leaf Oil adds a natural, earthy fragrance to products but has limited research on skin benefits and may cause irritation in sensitive individuals.

Skatole is a controversial fragrance ingredient with a strong fecal scent, used in tiny amounts to add complexity, but it can be irritating and is not for everyone.

A mild, natural-origin surfactant and scent ingredient that helps cleanse and lightly fragrance products, but may cause sensitivity in those allergic to citronella or related botanicals.

Sorbic alcohol is a mild fragrance ingredient and preservative helper, generally safe but with limited direct skin benefit.

Spanish Sage Leaf Oil adds a fresh herbal scent and may offer mild antimicrobial benefits, but it can be irritating for sensitive skin.

Spearmint Leaf Oil adds a fresh minty scent and mild antimicrobial benefits, but can be irritating for sensitive skin in high concentrations.

Spearmint oil adds a fresh minty scent and mild antimicrobial benefits, but can irritate sensitive skin at high concentrations.

This potent essential oil blend adds a warm, spicy scent and some antimicrobial activity, but it is a common skin irritant and sensitizer, especially at high concentrations.

A warming, aromatic oil blend that adds a spicy scent but can easily irritate sensitive skin.

Spike lavender oil adds a fresh herbal scent and may help calm skin, but it can be irritating for sensitive skin types.

Spiralene is a synthetic scent ingredient that adds a fresh, herbal note to products, but it offers no skincare benefits and may be a concern for those avoiding fragrance.

A synthetic scent ingredient that adds a warm, woody note but offers no skincare benefit and may be unnecessary for sensitive skin.

A synthetic fragrance ingredient that adds a woody, amber scent but offers no skincare benefits and may cause sensitivity in some people.

Spotted geranium oil offers a gentle astringent effect and a pleasant floral scent, but its skincare benefits are backed by limited research and it may cause irritation in sensitive individuals.

A fragrant essential oil with mild antioxidant potential, best suited for those who enjoy natural, woody scents and do not have sensitive skin.

Spruce leaf oil adds a fresh, forest-like scent to products but can be irritating for sensitive skin and is best used in low concentrations.

Spruce oil adds a fresh, woodsy scent to products but may irritate sensitive skin due to its essential oil content.

Star Anise Fruit/Seed Oil offers antimicrobial and soothing benefits but can be irritating for sensitive skin due to its essential oil nature.

Star Anise Leaf Oil adds a pleasant scent and some antioxidant benefits, but its essential oil nature means it can be irritating for sensitive skin.

Styralyl Alcohol is a synthetic fragrance ingredient that adds a light floral scent but may cause irritation in sensitive individuals.

A synthetic fragrance ingredient that adds a sweet, floral scent to products; generally considered safe at low concentrations but may cause sensitivity in some individuals.

This sulfurized limonene compound is rarely used in skincare and may cause irritation; it's best avoided in leave-on products.

A gentle, aromatic flower extract that adds a light citrus scent and mild soothing benefits to skincare formulas.

A fragrant, gentle essential oil that adds a pleasant scent and mild soothing benefits, but can irritate sensitive skin if used undiluted.

Sweet Orange Oil adds a bright citrus scent and mild astringent feel, but can irritate sensitive skin and increase sun sensitivity.

Sweet Orange Peel Oil adds a fresh citrus scent to products but can be irritating for sensitive skin and may increase sun sensitivity.

Sweet Violet Oil adds a delicate floral scent and potential soothing benefits, but is used in tiny amounts and may irritate sensitive skin.

Sweetgum oil adds a warm, balsamic scent to products and may offer mild soothing benefits, but it can be irritating for sensitive skin and is not well-studied in modern skincare.

A fragrant essential oil from Swiss stone pine that adds a fresh scent and may offer mild soothing benefits, but can be irritating for sensitive skin.

A fragrant essential oil from Swiss stone pine that adds a fresh, woodsy scent to products, but may cause irritation in sensitive skin.

A fragrant citrus oil with antioxidant potential, but may cause irritation in sensitive skin due to natural aromatic compounds.

A fragrant wood oil with limited research on skincare benefits; best appreciated for its scent rather than proven skin effects.