HI, Yes, bananas are a healthy fruit for someone with diabetes. They contain lots of potassium. Bananas sometimes get a bad rap though and people say they increase their blood sugars. Any fruit contains carbohydrates and carbs are what raises blood sugar levels. The amount of carbs in a whole banana is higher than another piece of fruit such as an apple. The serving size for a banana is either a small banana or half a regular/large banana. I would recommend getting some education from a Registered Dietitian about counting carbs for diabetes. That way you will know the amount of carbs to eat at each meal and how to work a banana into your meal plan.