Compound Monograph
Betulin
Betulin is a pentacyclic triterpene that makes up much of the white outer bark of birch trees.
Classification
Betulin is a triterpene, part of the terpenoids class. The largest class of plant compounds, built from five-carbon isoprene units — the essential-oil aromatics, resins, bitter principles, saponins, and plant sterols.
Where Does It Come From? (3)
Betulin is a naturally occurring triterpene, found in Birch bark, Shrubby bushclover and 1 other source. It is well tolerated orally (low toxicity).
Research & Evidence
Betulin is a pentacyclic triterpene alcohol that gives birch bark its characteristic white colour and can make up a substantial fraction of the outer bark by weight, which makes birch a convenient source for isolating it. It is the biosynthetic precursor of betulinic acid and is studied for anti-inflammatory and other activities, mostly in laboratory and animal models. It is also used in cosmetic preparations.
Toxicity & Safety
Betulin is poorly absorbed and has shown low toxicity in available testing, and birch bark extracts standardised to betulin have been used topically. Its safety in concentrated oral or long-term use is not fully characterised.