Masterwort Leaf Extract is a gentle botanical with potential soothing and antioxidant benefits, but research is limited and it's not a standout ingredient.
Irritation
low
Source
natural
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
Masterwort Leaf Extract is a gentle botanical with potential soothing and antioxidant benefits, but research is limited and it's not a standout ingredient.
Irritation
low
Source
natural
A gentle, water-based extract from mastic tree resin that may help calm irritation and provide antioxidant protection.
Irritation
low
Source
natural
A fragrant essential oil with antioxidant potential, but may irritate sensitive skin and is best used in low concentrations.
Irritation
moderate
Source
natural
A gentle, plant-derived wax that adds structure and a smooth feel to balms and creams without common irritation.
Irritation
low
Source
natural
A gentle, plant-based antioxidant that helps protect skin from environmental stress while offering mild soothing benefits.
Irritation
low
Source
natural
Mastic Thyme Flower Oil offers antimicrobial and antioxidant benefits but can be irritating for sensitive skin due to its essential oil nature.
Irritation
moderate
Source
natural
Mastic thyme oil offers antimicrobial and antioxidant benefits but can be irritating for sensitive skin; use in low concentrations.
Irritation
moderate
Source
natural
A gentle botanical extract with antioxidant and soothing potential, but human skin research is still limited.
Irritation
low
Source
natural
A gentle botanical extract with potential antioxidant and soothing benefits, though research is limited.
Irritation
low
Source
natural
Matrine is a plant-derived alkaloid that helps calm redness and irritation, making it a gentle option for sensitive or acne-prone skin.
Irritation
low
Source
natural
A gentle, antioxidant-rich ferment from a rare mushroom that may help calm skin and defend against environmental stress.
Irritation
low
Source
natural
A gentle, antioxidant-rich mushroom ferment that may help calm skin and defend against environmental stress.
Irritation
low
Source
natural
A gentle, antioxidant-rich mushroom powder that may help soothe and protect skin, though research is still emerging.
Irritation
low
Source
natural
A gentle, lab-grown flower extract that may help protect skin from environmental stress and support a more even tone.
Irritation
low
Source
biotech
A gentle, plant-based oil that helps soften and smooth skin without clogging pores, though research on its specific benefits is still limited.
Irritation
low
Source
natural
A nourishing, plant-based butter from Madagascar that softens and conditions skin, but may be too rich for oily or acne-prone skin.
Irritation
low
Source
natural
A gentle microalgae extract that may help calm skin and fight oxidative stress, but research is still early.
Irritation
low
Source
natural
A gentle, biotech-derived ferment that may help hydrate and support the skin barrier, but research is still early.
Irritation
low
Source
biotech
A gentle, antioxidant-rich bark extract from the Amazon with emerging research on soothing and protecting skin.
Irritation
low
Source
natural
A plant extract with promising antioxidant and soothing potential, but research in cosmetic use is still limited.
Irritation
low
Source
natural
MDM Hydantoin is an effective preservative but may irritate sensitive skin due to its slow release of formaldehyde.
Irritation
moderate
Source
synthetic
A synthetic preservative that helps keep products fresh but may cause irritation in sensitive skin.
Irritation
moderate
Source
synthetic
A gentle synthetic surfactant that helps cleanse and emulsify without stripping the skin's natural moisture barrier.
Irritation
low
Source
synthetic
MEA-Benzoate is a synthetic preservative helper that extends shelf life but may cause irritation for sensitive skin.
Irritation
moderate
Source
synthetic
MEA-Biotinate is a gentle, water-soluble form of biotin that may help strengthen hair and improve skin barrier function, but research is limited.
Irritation
low
Source
semi-synthetic
MEA-Borate is a mild pH adjuster that helps keep your skincare products stable and gentle, but it is not a star active ingredient.
Irritation
low
Source
synthetic
A strong synthetic cleanser that effectively removes dirt and oil but may be drying or irritating for sensitive skin.
Irritation
moderate
Source
synthetic
A gentle coconut-derived surfactant that helps create a rich lather while being less harsh than traditional sulfates.
Irritation
low
Source
semi-synthetic
A gentle emulsifier that helps create smooth, stable creams and lotions without common irritation.
Irritation
low
Source
semi-synthetic
A modified collagen that helps hair and skin feel smoother and more hydrated, but its large molecule size limits deep penetration.
Irritation
low
Source
semi-synthetic
A silk protein derivative that helps hair and skin feel smooth and hydrated, but evidence is mostly anecdotal.
Irritation
low
Source
semi-synthetic
A gentle chelating agent that helps your skincare products stay effective longer by neutralizing troublesome metal ions.
Irritation
low
Source
synthetic
A milder alternative to SLS that still provides good foam, but may still be drying for very sensitive skin.
Irritation
moderate
Source
synthetic
A gentle, sulfate-free surfactant that cleanses without stripping the skin, making it a good choice for sensitive or dry skin types.
Irritation
low
Source
synthetic
A mild sulfate-based cleanser that effectively removes dirt and oil but may still be drying for sensitive or dry skin types.
Irritation
moderate
Source
synthetic
A gentle synthetic surfactant that cleanses without stripping the skin, often used in sulfate-free and sensitive-skin formulas.
Irritation
low
Source
synthetic
MEA-Sulfite is a synthetic reducing agent used in hair treatments and some skincare, but it may cause irritation for sensitive skin.
Irritation
moderate
Source
synthetic
A mild cleansing agent with antimicrobial properties, best for rinse-off products and acne-prone skin.
Irritation
moderate
Source
semi-synthetic
A gentle botanical extract with antioxidant potential, but research on its specific benefits is still limited.
Irritation
low
Source
natural
A mild, plant-based exfoliant derived from meadowfoam seed oil that gently resurfaces skin without the sting of stronger acids.
Irritation
low
Source
natural
A silky, non-greasy emollient from meadowfoam seeds that hydrates and softens skin without clogging pores.
Irritation
low
Source
natural
A non-greasy, stable plant oil that hydrates and softens skin without clogging pores.
Irritation
low
Source
natural
A gentle, plant-based surfactant that cleanses without stripping the skin, making it ideal for sensitive and dry skin types.
Irritation
low
Source
natural
Conditioning agent
Meadowfoamamidopropyl PG-Dimonium Chloride
A gentle, plant-derived conditioning ingredient that softens hair and skin without heavy buildup or irritation.
Irritation
low
Source
semi-synthetic
A gentle botanical extract with soothing and antioxidant benefits, ideal for sensitive or irritated skin.
Irritation
low
Source
natural
A mild botanical water that can help calm and refresh skin, but its astringent properties may be too drying for very sensitive or dry skin types.
Irritation
low
Source
natural
A gentle botanical extract from meadowsweet root that may help calm skin and tighten pores, but research is limited compared to more studied soothing ingredients.
Irritation
low
Source
natural
Mealworm larva extract is an emerging, sustainable ingredient with potential moisturizing and antioxidant benefits, but research in human skincare is very limited.
Irritation
low
Source
natural
A gentle, antioxidant-rich plant extract from the Himalayas that may help calm and protect skin, though research is still early.
Irritation
low
Source
natural
A gentle, antioxidant-rich fruit extract that may help protect skin from environmental stress, though research is still emerging.
Irritation
low
Source
natural
MEL is an ambiguous label that likely refers to a melanin derivative or a typo; its benefits and safety are not well-documented.
Irritation
low
Source
mixed
A botanical extract with antimicrobial potential, but limited human studies and a risk of skin irritation at higher concentrations.
Irritation
moderate
Source
natural
A fragrant essential oil with mild antimicrobial potential, best used in low concentrations to avoid skin irritation.
Irritation
moderate
Source
natural
A gentle botanical extract with antioxidant potential, but research is limited compared to more common Melaleuca species.
Irritation
low
Source
natural
A gentle botanical extract with antioxidant potential, but research is limited compared to more studied plant extracts.
Irritation
low
Source
natural
A botanical essential oil with antimicrobial potential, but limited research and a risk of skin irritation for sensitive individuals.
Irritation
moderate
Source
natural
A gentle botanical extract with antioxidant potential, but research on its specific benefits for skin is still limited.
Irritation
low
Source
natural
Film Former
MELAMINE/RESORCINOL/ACRYLOYLDIMETHYLTAURATE/PEG-6 METHACRYLATE CROSSPOLYMER
A synthetic polymer that helps products stay put and feel smooth, but offers no active skin benefits.
Irritation
low
Source
synthetic
Melanin is a promising antioxidant and UV-protective ingredient, but its use in cosmetics is still emerging and not yet widely proven in human studies.
Irritation
low
Source
natural
A gentle botanical extract with antioxidant potential, but research on its skincare benefits is still limited.
Irritation
low
Source
natural