Beauty ingredients explained in plain English

Thiamine HCl is a gentle antioxidant that may help protect skin from environmental stress, but its benefits are less studied than other B vitamins like niacinamide.

A gentle, biotech-derived blend of vitamin B1 and yeast peptides that may help soothe and condition the skin, though research is still emerging.

Thianthol is a synthetic fragrance ingredient with limited safety data; it may cause skin irritation in sensitive individuals.

Thiazolylalanine is a novel synthetic antioxidant that may help protect skin from environmental stress, but research is still early and it's not a must-have ingredient.

Thimerosal is an effective preservative but controversial due to its mercury content; it is rarely used in modern skincare and is best avoided for sensitive or allergy-prone skin.

A gentle, hydrating biotech ingredient from a deep-sea microbe that may help calm irritation and support the skin barrier.

A synthetic preservative that can be effective but may cause skin irritation and has raised safety concerns in some regions.

A synthetic antioxidant that may help protect skin from pollution and UV damage, but research is still limited compared to more established antioxidants like vitamin C.

A powerful antioxidant that can help brighten skin and reduce signs of aging, but may cause irritation at high concentrations.

A lab-made peptide that may help improve skin firmness and reduce the look of fine lines, but research is still early.

A gentler, more stable version of alpha-lipoic acid that fights oxidative stress and supports skin radiance without the typical irritation of its parent molecule.

A hybrid peptide-antioxidant ingredient that may help firm skin and fight oxidative stress, but human data is still limited.

A synthetic peptide-lipoic acid hybrid that may help firm skin and soften lines, but human data is still limited.

A synthetic peptide that pairs lipoic acid with a tripeptide to help firm skin and fight oxidative stress, generally well-tolerated.

A synthetic peptide that combines a lipoic acid-like antioxidant with a signaling peptide to help protect and firm skin, though human studies are limited.

A next-gen hyaluronic acid that pairs deep hydration with antioxidant protection, but research is still early.

Thiodiglycol is a synthetic solvent and humectant that helps products spread smoothly, but it may cause mild irritation for sensitive skin.

Thiodiglycolamide is a synthetic brightener that may help fade dark spots, but research is limited and it can cause irritation for some.

Thiodiglycolic acid is a strong reducing agent used in professional hair treatments to alter curl or remove hair, but it can be irritating and is not for daily skincare.

A synthetic antioxidant that helps preserve product freshness and may offer mild skin protection, but it's not a star active ingredient.

Thioglycerin is a sulfur-based humectant that can soften and break down keratin, but it may cause irritation in sensitive skin.

Thioglycolic acid is a potent chemical that breaks hair structure for removal or perming, but it can irritate skin and requires careful formulation.

Thiohistidine is a gentle antioxidant that may help protect skin from oxidative stress and environmental damage, but research is still early.

Thiolactic acid is a gentle exfoliant that may help smooth skin and reduce signs of aging, but research is still limited compared to better-studied AHAs.

Thiomorpholinone is a synthetic fragrance ingredient with limited safety data; use with caution if you have sensitive skin.

Thiosalicylic acid is a stronger, sulfur-based cousin of salicylic acid that may help with acne and exfoliation, but it can be more irritating and is less studied in cosmetics.

A hybrid ingredient that combines silica's oil-absorbing power with thiosulfate's antioxidant potential, but research on its cosmetic benefits is still limited.

Thiotaurine is a gentle antioxidant that may help protect skin from environmental stress, but research is still early.

Thioxanthine is a synthetic antioxidant that may help protect skin from environmental stress, but research is limited and it's not a well-established ingredient.

A novel synthetic ingredient with limited public research; early data suggests it may help even skin tone, but its safety and efficacy are not yet well-established.

Threitol is a gentle, lesser-known humectant that helps hydrate skin without stickiness, but research on its cosmetic benefits is still limited.

A gentle amino-acid derivative that may help reduce visible skin reactivity and support a more even tone, though human data is still limited.

Threonine is a gentle, hydrating amino acid that supports the skin's natural moisture barrier and is well-tolerated by most skin types.

Thuja Bark Extract may offer soothing and antimicrobial benefits, but its use in skincare is still emerging and requires caution due to potential skin irritation.

A gentle botanical extract with antioxidant potential, but research on its specific benefits in skincare is still limited.

Thuja Leaf Oil offers antimicrobial benefits but can be irritating for sensitive skin; use with caution.

A traditional botanical extract with some antimicrobial promise, but limited modern research and a moderate risk of skin irritation for sensitive individuals.

A gentle plant extract with antioxidant potential, but research on its cosmetic benefits is still limited.

A gentle botanical powder with antioxidant potential, but research in cosmetics is still limited.

A gentle plant extract with antioxidant potential, but research on its skincare benefits is still limited.

A plant-based antioxidant extract that may help calm skin and fight free radical damage, though research is still early.

A gentle plant extract with antioxidant potential, but research is still early and benefits are not yet proven in human skin.

A gentle, antioxidant-rich botanical water that may help soothe skin, but research is limited.

A gentle botanical extract with antioxidant potential, but research on its topical benefits is still limited.

A plant extract with traditional astringent uses, but limited modern research on its effectiveness and safety in skincare.

A potent essential oil with antimicrobial potential, but its strong nature and limited skincare research mean it's best used cautiously in low concentrations.

Thujanol is a fragrant plant compound that can add a fresh, woody scent to products but may cause irritation for sensitive skin.

Thujic acid is a plant-derived compound with early evidence of antioxidant and antimicrobial benefits, but it is not well-studied in human skincare and is rarely used as a standalone active.

Thurfyl Nicotinate creates a temporary flush and warmth by widening blood vessels, but it is not a long-term solution for skin concerns and may irritate sensitive skin.

Thurfyl nicotinate HCl creates a temporary warming sensation by dilating blood vessels, but its cosmetic benefits are short-lived and may cause irritation in sensitive skin.

Thyme extract is a gentle botanical antioxidant that helps protect skin from environmental stress and may support a balanced skin microbiome.

Thyme extract is a gentle botanical antioxidant that may help protect skin from environmental stress, but its fragrance can be a concern for sensitive skin.

Thyme water is a mild, fragrant botanical water that can add a subtle antimicrobial boost and a pleasant herbal scent to skincare, but it is not a potent active ingredient on its own.

Thyme powder brings antioxidant and antimicrobial benefits to skincare, but its gritty texture limits it mostly to rinse-off products.

Thyme Leaf Extract is a gentle antioxidant that helps protect skin from environmental stress while offering mild soothing benefits.

Thyme Leaf Water offers a mild, natural way to add light antimicrobial and soothing benefits to skincare, but its effects are subtle and best for those who enjoy botanical ingredients.

Thyme oil can help fight acne-causing bacteria and provide antioxidant protection, but it is potent and may irritate sensitive skin if used undiluted.

A gentle, plant-based extract that may help calm skin and fight free radical damage, though research is still early.

Thymidine is a gentle, science-backed ingredient that helps support skin’s natural repair processes, making it a smart addition to anti-aging and recovery routines.

Thymine is a DNA base with emerging research in skin repair, but its cosmetic benefits are not yet well-established in human studies.