The insulin resistance diet -- book here:
http://www.amazon.com/Insulin-Resist.../dp/0071499849 -- is a diet that teaches you about low and high glycemic foods, how to "link" protein and carbs and fats together so that your blood sugar doesn't spike.
The theory is that if your insulin is spiking and crashing all the time, it's basically signaling to your body to store the excess glucose into fat. If your body doesn't have to send excess insulin into your system, then your body doesn't store your fuel (food) as fat, but rather you burn it off or it goes into muscle or other tissue.
So, for example, for every 25 g of carbs you eat, you need to eat AT LEAST -- minimum -- 7 grams of protein or more. The idea there is that the protein in that minimum quantity will help off set the insulin spike that the carb will cause in your body. The same thing applies to fats and the combination of foods.
Of course, the authors aren't saying eat a cupcake and then a 2 lbs piece of steak... they recommend eating low glycemic index foods like vegetables and low-sugar fruits with whole grains and lean proteins. And to exercise, since that helps balance the excess glucose created in your body (you burn it off exercising, rather than letting it be converted into fat in your body).