I myself don't believe insulin usage causes diabeties alone. Heredity has more to do with being a diabetic then using 10-20ius a day. If your family has a history of diabeties it may promote the disease. I could understand if you were constantly injecting insulin night and day. But the life of insulin in the body is around 4-8 hours depending what type you take. Saying that I feel safe using insulin for 4-5 weeks at a time. I've used it for 8 weeks and have had no problems whatsoever...