My point is that not all calories are equal as far as the consumer is concerned. As others have noted, eating RDI (or just under) with only carbs - eg the twin

My point is that not all calories are equal as far as the consumer is concerned. As others have noted, eating RDI (or just under) with only carbs - eg the twinkies diet - would be tiring and soul-destroying, likely very difficult to sustain. Eating the same amount (calories) of proteins and fats would keep you much happier and healthier. Eating a lot more (calories) of proteins and fats, and avoiding as many carbs as possible, and you're probably lose weight without having to track & maintain a 'caloric deficit' state.