Banaba leaf (corosolic acid)

Tier 2 — promising · Blood sugar · Insulin sensitivity

Contains corosolic acid, which activates glucose transporters to help cells absorb sugar more efficiently. A 2024 review of 7 trials found banaba leaf significantly reduces fasting blood sugar and post-meal glucose in people with type 2 diabetes and prediabetes. Effects are modest but consistent. Generally well tolerated with no serious side effects reported. Can enhance blood sugar medications.

Dose: 32–48 mg/day standardised to 1% corosolic acid; take before carbohydrate-containing meals