Banaba tea is a herbal tea made from the leaves of the banaba tree (Lagerstroemia speciosa Linnaeus), a perennial tree found natively in upland forests of the Philippines. Major commercial banaba plantations are found in Nueva Ecija, Pampanga, and Quezon provinces, exporting this tea to Japan, Korea and the USA. Banaba leaves can be harvested from mature trees every four months.
Medical studies quoted by the companies that sell banaba claim that colosolic acid in banaba leaves have a hypoglycemic effect, which can help control diabetes if ingested as part of a proper diet regimen.
Traditionally, banaba has been used by local herbalists (albularyos) as a remedy for kidney and bladder problems, stomach disorders and diarrhea. Several studies are being conducted to investigate its effects on blood pressure and kidney functions.
Info taken from local pamphlets printed by the Department of Trade and Industry and several companies that sell banaba tea.