Diabetes is a condition often caused when someone surpasses their personal fat threshold. This causes an accumulation of fat in the liver and pancreas, causing metabolic dysfunction. The cure is simple: lose fat.
In short, read the ingredient label of your favorite high-fiber protein bar. If it uses isomalto-oligosaccharides (IMOs), then it is best avoided. The FDA has ruled that IMOs have insufficient evidence to be claimed as a dietary fiber, and a handful of studies suggest that they are absorbed with similar efficiency as sugar.
Eat fibrous vegetables and proteins first during meals, saving your starches for last, and you can drastically reduce the blood glucose and insulin response to that meal.