Vitamin supplements for diabetes?

I’ve had type 1 diabetes for 51 years, and for the past 45 years I have been taking mega-doses of vitamins in the hopes of slowing the complications. Logically, since the process by which hyperglycemia causes complications is inflammation, and since many vitamins, such as vitamin E, are anti-inflammatories, vitamins should help. I don’t know whether my long survival with the disease has anything to do with the vitamins, since you can’t prove a cause by looking at just one case, but people do say I look a good 20 years younger than I actually am.