Plant extracts
Willow bark extract
Also listed as Salix alba bark extract, white willow bark
A plant extract sold as 'natural BHA'. Its salicin is not meaningfully converted to salicylic acid in skin; expect a mild soothing extract, not an acne treatment.
What it is
Willow bark contains salicin and other salicylates plus polyphenols. Salicin becomes salicylic acid in the gut and liver when you swallow it, but there is little evidence skin converts it to any useful degree, so a willow bark 'BHA' is not equivalent to salicylic acid.
In formulas it adds mild anti-inflammatory and antioxidant activity seen in cell studies.
How strong is the evidence?
Weak evidenceEvidence is limited to cell and lab studies showing anti-inflammatory effects, plus small manufacturer-run studies of salicin products. No controlled trials show willow bark extract clears acne or exfoliates like salicylic acid.
What it's used for, checked
Natural substitute for salicylic acid
UnprovenContains salicin, but there is no good evidence skin turns it into salicylic acid or that it matches salicylic acid's effect.
Soothing redness
UnprovenAnti-inflammatory in cell studies only.
Who should be careful
- People with aspirin or salicylate allergy should be cautious.
- Plant extracts can cause contact allergy; patch test if your skin is reactive.