In his book Carrots and Sticks: Unlock the Power of Incentives to Get Things Done, Ian Ayres, a contracts professor at Yale Law School, writes about an interesting insight that he had regarding his own weight loss efforts. After numerous but only temporarily successful efforts, he finally had a realization. He knew, unfortunately, how to eat in a way that kept his weight around 210 or so (I can’t remember the exact number). He also knew how to eat in a way that brought his weight down to around 170 (or so), although he couldn’t sustain it for more than a few months. But he didn’t know how to eat for 190 pounds.

And so, he was doomed to see-saw back and forth until he finally figured that out. And it wasn’t until he learned this that he was finally able to sustain his new reduced weight. Although it wasn’t exactly the goal weight he had originally set, it was, on the other hand, permanent.

The research has shown, over and over, that most dieters are capable of sustaining a weight loss of no more than 10% over the course of a year. This is true across all kinds of programs, no matter how well known.

I believe that we will someday understand a biochemical basis for this. The question that I continue to ask myself is whether a person can spend sufficient time at their “compromise position” weight to establish it as a new baseline weight from which it might be possible to lose another 10% successfully and permanently.

Of course this approach requires a fair amount of patience and perseverance, both of which tend to be in short supply in people who want to lose weight. I still believe there is a neurochemical underpinning to this, which is why I counsel people not to focus on their weight.

Instead of weight, I focus on just two things. The first is to concentrate as much as possible on productive choices and not to sweat it if you’re successful only 50% or 75% or 90% of the time, let’s say. I’d rather have people identify the single least healthful activity in which they engage, and then work to decrease the number of ounces of soda or chips they eat on a daily, or weekly, basis. I encourage them to see where things stand in a few weeks or months. Their very best has got to be better than their current eating pattern, and it’s essential to remember that 100% is neither necessary nor practical.

Secondly, for people who like having something to measure, I recommend getting a tape measure instead of a scale. If you want to see how you’re progressing, check your waistline. To me that’s a much more valuable measurement. I really don’t care how much people weigh; I want to know how their pants fit.

As pants continue to fit better and better, weight begins to fall. When that happens I have seen the rest take care of itself. It may translate into “only” a 10% weight loss, but it will be real and permanent.