Well, the first days are the hardest days,
Don't you worry any more.
'Cause when life looks like Easy Street,
There is danger at your door.
--The Grateful Dead, Uncle John's Band
No matter how long or severe your diet, the first 72 hours are the worst. This unfortunate fact leads many people to abandon diets which, if continued, would soon yield sustainable weight loss without undue discomfort. Once you've surmounted the difficult period at the start of a diet, you can be assured the worst is behind you; it's unlikely you'll experience anything that bad for the rest of its course. Humans may have a limitless ability to ignore unpleasant facts, but we're also able to endure truly awful realities: high school, boot camp, root canals, going public, life--as long as we know it's only for a while and we'll never have to do it again.
Planning a diet from an understanding of how weight loss really works gives you a handle on how long you'll have to endure its unpleasantness. Knowing how feedback can control your weight equips you with at least intellectual confidence that once you've lost weight you'll never have to go through that again. As you see the trend line in action, your initial confidence will increase as experience confirms theory, logic, and calculation.
In this section we'll look at the mechanics of getting a diet underway, why the first days are the hardest days, and how to get through them to the easier part beyond.