La
Lanolin
Lanolin · Lanolin AlcoholBarrier
Sheep-derived occlusive wax. Excellent moisture-sealing properties, but a known allergen for a small subset of users.
What it does
Lanolin is the wax sheep secrete to waterproof their wool. As a skincare ingredient it's one of the most effective occlusives — it can hold roughly twice its weight in water and forms a flexible film without the heaviness of petrolatum. It's also one of the more common cosmetic allergens. Patch test is standard practice if you've reacted to balms or pharmacy moisturizers in the past.
The evidence, graded
expert consensusFungal acne (Malassezia folliculitis) is fed by fatty acids and esters with C11-C24 chain lengths. Many oils marketed as 'safe for acne-prone skin' make fungal acne worse. Squalane, MCT, and mineral oil are typically tolerated.Rubenstein 2014 · Journal of Clinical and Aesthetic Dermatology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
wool wax, wool grease
Pairs worth knowing
This page is public and indexed on purpose (unlike profiles and drops, which are unlisted) — it’s the citation behind shared ingredient cards, and it should be findable.
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