&gt; Like I said, it doesn&#x27;t matter if you&#x27;re in a car that gets 30mpg or one that gets 50mpg<p>But what if the car adjusts its fuel efficiency dynamically?  If that&#x27;s the case, it might be something worth investigating and understanding, no?<p>&gt; Stop trying to make this harder than it needs to be, or more complicated that it needs to be.  Consume less calories than you burn, and in the long run you will lose weight.<p>Correct, but if certain levels of caloric deficit can cause physiological changes that affect rate of weight loss, altering the <i>difficulty</i> of losing weight, why be opposed to discussing that idea?  Why not maximize efficiency of weight loss?