A gentle, protein-based conditioning ingredient that adds softness and manageability without heavy buildup.
Irritation
low
Source
semi-synthetic
Beauty ingredient research
Browse the review database to understand what an ingredient is, what it does in a beauty formula, when it is useful, and when it deserves caution across skincare, haircare, bodycare, makeup, and more.
20769
Reviewed ingredients
524
Low-concern standouts
2884
Need usage caution
A gentle, protein-based conditioning ingredient that adds softness and manageability without heavy buildup.
Irritation
low
Source
semi-synthetic
A gentle, protein-based conditioning ingredient that adds softness and manageability to hair and skin without heavy buildup.
Irritation
low
Source
semi-synthetic
A synthetic film-former that helps products stay put, but it can feel tight or dry on some skin types.
Irritation
low
Source
synthetic
A gentle collagen derivative that adds a light film to skin, helping it feel smooth and hydrated without heavy residue.
Irritation
low
Source
semi-synthetic
A semi-synthetic collagen derivative that forms a light film on skin to help retain moisture, but research on its benefits is still limited.
Irritation
low
Source
semi-synthetic
A gentle plant extract with antioxidant and soothing potential, though research is still early.
Irritation
low
Source
natural
A fermented botanical extract that soothes and protects skin with antioxidants, ideal for sensitive or stressed skin.
Irritation
low
Source
biotech
A gentle plant extract that may help calm skin and fight free radical damage, though research is still early.
Irritation
low
Source
natural
A gentle, plant-derived antioxidant that helps protect skin from environmental stress without irritation.
Irritation
low
Source
natural
A traditional plant extract with potential soothing benefits, but research is limited and it's not a mainstream ingredient.
Irritation
low
Source
natural
Amyl acetate is a synthetic fragrance ingredient with a fruity scent; it can be irritating for sensitive skin in high concentrations.
Irritation
moderate
Source
synthetic
Amyl alcohol is a solvent that helps dissolve other ingredients, but it can be drying or irritating for sensitive skin at higher concentrations.
Irritation
moderate
Source
synthetic
Amyl benzoate is a synthetic fragrance ingredient that adds a pleasant scent to products, but it offers no direct skin benefits and may cause sensitivity in some individuals.
Irritation
low
Source
synthetic
Amyl Butyrate adds a sweet, fruity scent to products but offers no skincare benefits; it's generally safe at low levels but may cause irritation in sensitive individuals.
Irritation
low
Source
synthetic
A common synthetic fragrance allergen that can cause skin reactions in sensitive individuals, but is generally safe for most people at low concentrations.
Irritation
moderate
Source
synthetic
Amyl Cinnamate is a synthetic fragrance ingredient that adds a sweet, floral scent but offers no skincare benefits and may be a concern for those with fragrance sensitivities.
Irritation
low
Source
synthetic
A synthetic fragrance ingredient that adds a floral jasmine note; generally safe at low levels but may cause sensitivity in some individuals.
Irritation
low
Source
synthetic
Amyl ethyl ketone is a synthetic fragrance ingredient that adds a fruity, spicy scent but offers no skincare benefits and may cause sensitivity in some individuals.
Irritation
low
Source
synthetic
Amyl formate is a synthetic fragrance ingredient that adds a fruity, apple-like scent to products; it is generally considered safe at low concentrations but offers no skincare benefits.
Irritation
low
Source
synthetic
Amyl Hexanoate is a safe, fruity-smelling synthetic ester used to add a pleasant apple-like scent to cosmetics, with a low risk of irritation for most people.
Irritation
low
Source
synthetic
Amyl isobutyrate is a synthetic fragrance ingredient that adds a fruity, sweet scent but offers no skincare benefits.
Irritation
low
Source
synthetic
Amyl Isovalerate is a synthetic fragrance ester that adds a fruity, apple-like scent to products, but offers no skincare benefits and may cause sensitivity in some individuals.
Irritation
low
Source
synthetic
A lightweight, non-greasy emollient that helps soften skin and improve product texture without clogging pores.
Irritation
low
Source
synthetic
Amyl phenylacetate is a synthetic fragrance ingredient that adds a sweet, honey-like scent to products; it is generally considered safe at low concentrations but may cause sensitivity in some individuals.
Irritation
low
Source
synthetic
Amyl Propionate is a synthetic fragrance ingredient that adds a fruity, apple-like scent, but offers no skincare benefits and may cause sensitivity in those with fragrance allergies.
Irritation
low
Source
synthetic
Amyl Salicylate is a synthetic fragrance ingredient that adds a sweet, floral scent to products; it is generally considered safe at low concentrations but may cause sensitivity in some individuals.
Irritation
low
Source
synthetic
A lightweight, non-greasy emollient that softens skin without clogging pores, ideal for oily or combination skin types.
Irritation
low
Source
synthetic
Amylase is a gentle enzyme exfoliant that dissolves dead skin cells by breaking down surface starches, making skin smoother without harsh scrubbing.
Irritation
low
Source
biotech
A synthetic floral scent ingredient that may cause skin irritation or allergic reactions in sensitive individuals.
Irritation
moderate
Source
synthetic
A synthetic fragrance ingredient that provides a jasmine-like scent but may cause skin irritation in sensitive individuals.
Irritation
moderate
Source
synthetic
A synthetic UV filter that also contributes to fragrance; effective but may cause sensitivity in some individuals.
Irritation
moderate
Source
synthetic
A common synthetic fragrance ingredient that adds a floral scent but is a known allergen for some people, especially those with sensitive skin.
Irritation
moderate
Source
synthetic
Amylcinnamyl alcohol is a common synthetic fragrance that adds a sweet floral scent, but it is a known allergen that may cause skin reactions in sensitive individuals.
Irritation
moderate
Source
synthetic
Amylcyclopentanone is a synthetic scent ingredient that adds a pleasant floral-fruity note, but it offers no skincare benefit and may cause sensitivity in those with fragrance allergies.
Irritation
low
Source
synthetic
Amylcyclopentenone is a synthetic fragrance ingredient that adds a sweet, floral scent but may cause skin irritation in sensitive individuals.
Irritation
moderate
Source
synthetic
Amylfuran is a synthetic fragrance ingredient with limited safety data; it may cause skin irritation in sensitive individuals.
Irritation
moderate
Source
synthetic
Amylisoeugenol is a synthetic fragrance compound that adds a warm, spicy scent but may cause skin irritation or allergic reactions in sensitive individuals.
Irritation
moderate
Source
synthetic
A gentle enzyme exfoliant that dissolves dead skin cells without scrubbing, ideal for sensitive skin.
Irritation
low
Source
biotech
A gentle, plant-derived film-former that helps products feel smooth and can provide a light, non-sticky barrier on skin.
Irritation
low
Source
natural
Amylose is a gentle, natural starch derivative that helps create a smooth, lightweight film on the skin, improving texture and moisture retention without clogging pores.
Irritation
low
Source
natural
Amylvinyl carbinol is a natural mushroom-derived alcohol used mainly for scent, with some early research suggesting mild antimicrobial benefits, but it can be a skin sensitizer for some.
Irritation
moderate
Source
natural
A synthetic fragrance ingredient that adds a pleasant scent but may cause irritation in sensitive individuals.
Irritation
moderate
Source
synthetic
A natural essential oil with a warm, woody scent that may offer mild skin-soothing benefits, but can cause irritation in sensitive individuals.
Irritation
moderate
Source
natural
A synthetic peptide blend that may help improve skin firmness and reduce fine lines, but more human studies are needed to confirm its effects.
Irritation
low
Source
synthetic
Anti-aging agent
Anacardoyl SH-Pentapeptide-39 Tripeptide-1
A synthetic peptide blend that may help support collagen and improve skin firmness, but human data is still limited.
Irritation
low
Source
synthetic
A promising peptide that may help firm skin and soften lines, but more human studies are needed to confirm its effects.
Irritation
low
Source
semi-synthetic
A synthetic peptide that may help improve skin firmness and reduce fine lines, but research is still emerging.
Irritation
low
Source
synthetic
A natural exfoliant from clam shells that gently polishes skin, but may be too scratchy for sensitive or compromised skin.
Irritation
moderate
Source
natural
A gentle, antioxidant-rich bark extract that may help calm and protect skin, though research is still early.
Irritation
low
Source
natural
A mineral-rich volcanic rock extract that may support skin barrier function, but research is limited and benefits are not well-established.
Irritation
low
Source
natural
A gentle Amazonian oil that hydrates and soothes, ideal for dry or sensitive skin.
Irritation
low
Source
natural
A gentle, natural seed powder that helps exfoliate and absorb excess oil without harshness, but research on its specific benefits is still limited.
Irritation
low
Source
natural
A plant-derived compound with promising antioxidant and soothing benefits, though research in topical skincare is still emerging.
Irritation
low
Source
natural
A gentle alpine plant extract that may help calm irritated skin and provide antioxidant protection, though research is still emerging.
Irritation
low
Source
natural
A gentle plant extract with antioxidant potential, but research on its specific benefits for skin is still limited.
Irritation
low
Source
natural
A gentle, plant-derived extract with antioxidant and soothing potential, though research is still early.
Irritation
low
Source
natural
A gentle, plant-derived extract with antioxidant and soothing potential, though research is still early.
Irritation
low
Source
biotech
Anemarrhena Root Extract is a gentle botanical with antioxidant and soothing potential, but human skin research is still limited.
Irritation
low
Source
natural
Anethole adds a sweet, licorice-like scent to products but can be irritating for sensitive skin at higher concentrations.
Irritation
moderate
Source
natural
A gentle botanical extract with antioxidant potential, but research is limited compared to more established plant extracts.
Irritation
low
Source
natural