Banaba leaf extract’s key components include corosolic acid, lagerstroemia, and gallotannins.
Corosolic acid lowers glucose levels in the bloodstream through a variety of mechanisms. It:
Activates cells in the body to take up higher amounts of glucose .
Discourages the body from breaking down starches or sucrose into glucose molecules.
Prevents the body from making glucose for energy from non-carbohydrates (opposes gluconeogenesis).

It also lowers fat levels (triglycerides and LDL).Lagerstroemia is an ellagitannin, a type of molecule that is present in many common fruits and nuts such as pomegranates, strawberries, and almonds.
 Lagerstroemia increases glucose transport activity by activating glucose transporters (GLUTs) and promoting more signaling (transmission) molecules to be made. Transmission molecules like Nf-kB and MAPK, along with GLUTs, all help cells to absorb glucose and use it for energy .

PGG, one of the key gallotannins responsible for banaba’s anti-diabetic benefits, discourages fat cell production (adipogenesis). Gallotannins are a type of tannic acid, which is the same component that also enables red wine to lower blood sugar levels.