These health claims have not been yet tested in clinical trials. Even within the practice of Ayurvedic medicine, there are controversies about the composition (amlaki, haritaki and bibhitaki), preparation, and medicinal uses of Triphala.
The active constituents are unknown. Triphala contains several compounds that have been proposed to be responsible for its claimed health benefits, including gallic acid, chebulagic acid, and chebulinic acid. 
Contemporary research on triphala
There is preliminary evidence that Triphala contains compounds with antioxidant properties in isolated cells and rats, however this has not yet been demonstrated in people.
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