How much weight do you have to lose? Mark says in the book that days of less than 50g of carbohydrates should be limited to a few times a week, not every day in perpetuity. 50 - 100 grams is the sweet spot, and I can attest to that. <50g wasn't doing anything for me once I got down to the last 20 or so pounds to lose. But over the past couple of weeks I've been upping my daily carb intake and have noticed a difference. Are you diabetic? If so, could you have Dawn Phenomenon? The other thing I can think of is that vegetables are so high in nutrients that unless you are eating free-range, grass-fed meat every day, you are not getting the nutrients you need and so your body is in conservation mode. And even then, you could be lacking.