Banaba

Lagerstroemia speciosa

Snapshot

Indications	Contraindications
Prediabetes^{1, 2} Impaired fasting glucose³ Metabolic syndrome⁴ Insulin resistance⁵ Serum triglycerides⁴	Pregnancy⁶ Lactation⁶

Banaba (Lagerstroemia speciosa) is a tropical tree whose leaf extract, standardized to corosolic acid and ellagitannins, has been used in folk medicine for diabetes and acts through improved cellular glucose uptake and slowed starch and sucrose digestion⁷. Supplementation is used for glycemic control and insulin resistance in prediabetes^{1, 2}, for features of metabolic syndrome such as blood pressure and triglycerides, and for weight management. The typical patient has impaired fasting glucose or impaired glucose tolerance, often with overweight or metabolic syndrome³.

Human research is limited to about a dozen small trials, mostly in prediabetes, metabolic syndrome, polycystic ovary syndrome, and weight management. Banaba alone has been tested in a single small placebo-controlled trial in metabolic syndrome, which found lower fasting glucose, triglycerides, and systolic blood pressure⁴. Most other trials test combinations, so effects cannot be attributed to banaba itself. In postmenopausal women with overweight or obesity, a 2025 retrospective observational study of banaba combined with myo-inositol found lower insulin resistance, and no controlled trial has confirmed it. Products are mainly leaf-extract capsules, powders, and liquids, with many combination formulas pairing banaba with berberine, gymnema, or chromium; 476 products list banaba, and Form comparison covers the differences.

Last updated October 16, 2026. Read how we make monographs.

In the full monograph

25 sources, 23 studies

When to useThe situations practitioners use it for, each with the reason and the study behind it.
SafetyWho should avoid it, who needs extra care, and the side effects reported in studies.
InteractionsThe medicines and supplements it interacts with, the effect of each, and what labeling says to watch.
Protocol notesThe doses used in studies, how and when they were taken, and how the forms on the market compare.
How it worksWhat it is and how it works in the body, in plain terms.
Published studiesThe studies behind each use, popular claims checked against them, and trials still under way.
Word of mouthWhat patients and practitioners report online, kept separate from the clinical evidence.
Clinical perspectiveA closing read of where the evidence is solid, where it is thin, and what has not been studied.

Snapshot

In the full monograph

Sources