One thing is for sure, we're all different. I have responded beautifully to Atkin's and it has totally lifted the fog and slowness. If you are not losing you have several ways to look at it, insulin is not the problem for you something else is, or you might not be following the diet quite correctly--misinterpretation of something, or you may have a medical problem like medications that interfere, thyroid problem etc. I'd go see an endocrinologist who is Atkin's friendly (now there's a task!), it was incredibly revealing for me. Expensive yes. Worth every little penny.