I'm sorry if have some incorrect information. I don't have diabetes, but in my family there are several people with pre-diabetes. Now, if I understand correctly, you can reverse the process by eating healthy, exercising etc. But there is also a point of no return, where you can't fix your body anymore.
I'm not biology major, but I was always fascinated by science explanations. My friend is a biology major, and she told me something about receptors, but couldn't remember the exact stuff they were taught in school.
Anything from straight up explanation, link to articles or research papers (open, I don't have logins for paywalls), or even just some ELI5 thing would be OK. Also, if I have some misconception, and diabetes is reversible (without some miracle drug, just by the same things - eating healthy and doing sports), I'd be happy to hear.
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