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Willow Bark Extract
Salix Alba (Willow) Bark Extract · Salix Nigra (Willow) Bark ExtractExfoliant
Natural source of salicin, which converts to salicylic acid on the skin. Marketed as a natural BHA, but the conversion is partial.
What it does
Willow bark contains salicin, a precursor that the body partially converts to salicylic acid. Topically the conversion rate is modest, so willow bark extract is a weaker exfoliant than direct salicylic acid at comparable concentrations. Useful in 'natural BHA' positioned products, but if you need real BHA performance, salicylic acid is the more reliable pick.
The evidence, graded
expert consensusOTC salicylic acid in the US is capped at 2% for acne and 3% for body/scalp uses under the FDA monograph. Higher concentrations (often used in-office for chemical peels or for keratosis pilaris/warts) are prescription or professional-only.FDA 2010 · 21 CFR Part 333 Subpart D ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
salix alba bark extract
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