I have had T1D for just short of 42 years. I don't really have any complications, though it has caused me some stress over the years, which seems to reduce significantly the longer I use Freestyle Libre. All that stress has created quite a few complications, but I don't think they are the ones you're asking about.
I wouldn't put it down to brilliant control though, though I don't know really. For some reasons I seem to remember the high blood sugars far more than the normal range blood sugars, looking back I can't remember any, but there must have been some. I just don't remember them, so I might be thinking my control was worse than it really was.
However, there are three things that I think have been important, as well as reasonable blood sugar control. One is luck, some people are just luckier with their genes than others. I think some people are just more prone to some complications.
Another is I've always walked a lot, and the third is that I have always really liked fruit and veg, and eat a lot of it. The bio-active compounds in fruit and veg, are apparently neuro-protective.
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