As a type 1 diabetic, and also an ex-Royal Marine who was fairly fit and healthy – I never understood why I wasn’t overweight, but many type 2 diabetics were.
The basic reason, is that insulin is also the ‘fat hormone’ – it signals the body to store excess sugars as fat. And type 1 diabetics don’t produce insulin. But type 2 diabetics do produce insulin, but it isn’t absorbed – and so sits in the blood stream – which causes the body to lay down fat.
I noticed in myself, that if I ate more carbs, and therefore needed to inject more insulin – I also gained weight. When I went low card, I used less insulin, and lost weight.
For a type 2 – what’s of primary importance, is to reduce insulin sensitivity. the best way to do this – is with exercise. I see a dramatic difference in the amount of insulin I need for 1 gram of carbs – depending on whether I’m actively exercising or not. When I exercise, my insulin resistance drops – or to put it another way – my insulin sensitivity increases. So I need less insulin for the same amount of food. Less insulin, means less fat being deposited in your body.
Seriously – some simple exercise to lower your resistance/increase your sensitivity – will cause you to lose weight.
I did an experiment once – after dropping of a rental car in my local city, I decided to run home, instead of using transport. It was about 7 miles. The next day, I had to half my insulin requirements, and the effect lasted for over a week, with no more exercise.