@Jalima
There is an awful lot which is still not understood about nutrition. I developed Type 2 diabetes when I was in my early 30s, despite never having been obese. I am usually a healthy weight, although I struggle not to become overweight. When I was first diagnosed, I had consultant care at a specialist unit and I was part of all sorts of research trials, but nobody could tell me why I had developed diabetes. Thirty years later, I wish I still had that level of care, because research has progressed and maybe somebody could provide some answers. As it is, I've experimented with what works best for me regarding food. There's nothing I don't eat, but I find that restricting carbs to below 75 a day (as far as possible) and eating fats (mainly healthy ones) works best. I've fallen out with so many dieticians who have told me that I should be eating less fat and more starchy carbs. The link to artificial sweeteners is interesting, because I used to use them quite a lot.
Interestingly, medical researchers are beginning to say what I've been saying all along, namely that fat helps regulate blood glucose levels. (sigh) I obviously missed my vocation.