Blood Sugar + GI/Foods as it relates to fuel utilization

Been reading a bit about how when the body’s blood sugar level is kept lower carbohydrates won’t be as likely to be used as energy which in theory means you’d be able to burn off body fat quicker.

I just wanted to get some feedback from others with more knowledge than myself on controlling blood sugar level via watching the GI of foods you have in your diet and how that may or may not relate to fat loss.

Thanks !