I'm reading Richard Bernstein MD's "THE DIABETES DIET" as he has had Type 1 since he was 12 and he is a healthy 78 now. He says that ALL obese people will get Type 2 diabetes if we stay that way long enough as we are all INSULIN RESISTANT. He explains why we don't lose weight on regular diets (Insulin is the FAT STORING hormone and when it is in the blood we don't burn fat.)
He has lectures on YouTube and I recommend him highly. I've learned so much.