In Suriname where I worked for 7 years as a physician- I saw that -especially the Hindustani population[from India ]often used bitter melon[looks like a “rimpled” cucumber] as a treatment for diabetes. I was not into “herbs” at that time. The vegetable is extreme bitter
There are of course in any country/culture many foods/herbs for diabetes.
Momordica has been evaluated in modern medicine [and many other herbs not]
Momordica has also shown clear anticancer properties.
Interesting that this is the case with many anti-diabetes herbs and even with the drug metformin that is developed for a plant

Up to 3x per day one or less