Karela in any form is not a treatment for diabetes and it has no proven role for lowering your blood sugars.But if you take it at any snack time ,you sure can reduce the extra calories that go in on snacking on other items. Plus it will give you vitamins and minerals. So Karela in any form is a healthy component of a diabetic diet but it does not reduce sugars per se

Dear Ma’am There is no evidence to suggest that Karela powder or karela in any other form like juice will control your diabetes. Please read this https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3307184/