They’re The Obstacle. — So what is a diet? I like to call it living out bad ideas over and over again and expecting a permanent result. Why is that important? Well, number one, companies are marketing themselves with greater and greater frequency as a response to the anti-diet backlash as not a diet when they are absolutely and totally a diet. The problem is that most of us don’t actually know what a diet is, or if we think about weight loss, we think, well, I have to have a diet, ‘let me go do this unpleasant thing to have the result I’m looking for.’