Banaba (Corosolic Acid)
Blood sugar
A Filipino leaf extract whose corosolic acid mildly mimics insulin. Useful adjunct in blood sugar management; lacks the GI burden of berberine.
EvidenceLimited
Small RCTs support modest blood sugar improvement in T2D. Gentler effects than berberine. Effects: 4–8 weeks.
Lagerstroemia speciosa (banaba) leaves contain corosolic acid, a triterpene that improves glucose uptake in muscle cells and has been called 'plant insulin.' Used in traditional Filipino medicine for diabetes. Modern human trials are small but supportive: modest HbA1c reduction, improved post-meal glucose. Gentler on the gut than berberine, easier to combine with other supplements.
- Form
- Banaba leaf extract standardised to 1–2% corosolic acid (GlucoTrim, GlucoFit).
- Dose
- 32–48 mg corosolic acid daily (typically delivered via 250–500 mg of standardised extract). Split before meals.
- Timing
- Before main meals.
- Schedule
- Daily.
- Side effects
- Generally well-tolerated. Hypoglycemia in diabetics on medication.
- Interactions
- Diabetes medications — additive.
- Contraindications
- Active hypoglycemia. Pregnancy / breastfeeding.
- Lab markers
- Fasting glucose, HbA1c.
- Food sources
- Banaba leaves are used in traditional Filipino teas.
Pairs with
Berberine, chromium, gymnema (metabolic stack).
within Herbs & botanicals