&gt; then I was definitely eating 4000+ calories per day and not getting Fat<p>I&#x27;m not sure about that... allegedly, research suggests that most people have the same BMR (basal metabollic rate), and that there is nothing like &quot;fast metabolism&quot; (i.e. people get rougly equal amounts of energy from food).<p>What I was referring to above, and what the article referrs to (with Glicemic Index) is purely psychological - how much food you want to eat, and how hungry&#x2F;satiated you feel. I&#x27;m still pretty sure that calories-in&#x2F;calories-out theory is more-or-less correct.