Monday, April 14, 2008

Weight loss success: a teaser

In the "requests" posts, someone asked me to write about the issue of the success rate for weight loss maintenance. This is something I wondered about myself. I'd heard the factoid that "95% of dieters regain the weight within five years" but was not familiar with the actual scientific literature on the subject.

Now, having familiarized myself somewhat...I still have no idea what the success rate is for weight loss. The literature is a mess.

A big part of the problem is that different studies use different measures of "significant weight loss" and "long term." Is "significant weight loss" a certain number of pounds, maybe 20, or 30, or 50? Or a certain percentage of your starting body weight? And is "long term" one year, or two, or ten? There are also qualitative differences in studies looking at different kinds of weight loss. Some studies look at people who started out morbidly obese and others looked at weight loss in those who started out merely overweight. Some studies look at weight loss through diet alone, others through exercise alone, and some through a combination of the two. Some of the diets studied are moderate, and some actually involve medically-supervised fasting conditions. The weight loss interventions studied vary in their durations, as well.

So some studies say that the rate of long-term weight loss success is 2% (1) and others say it is 20% (2). At any rate, I think it's safe to say that the rate of success at long-term maintenance of significant weight loss is greater than 0% and less than 100% and instead of further dissecting the matter, I think it's more instructive to focus on studies looking at variables that predict success in long term maintenance of weight loss. Weight loss maintenance may truly not be feasible for all or even most people, but I still think dissecting out factors that can contribute to maintenance of long-term weight loss is useful.

And that's what I'm going to post about on Monday...

1. Stunkard AJ, McLaren-Hume M. The results of treatment for obesity. Archives of Internal Medicine 103: 79-85, 1985.

2. Wing RR and Phelan S. Long-term weight loss maintenance. American Journal of Clinical Nutrition, 82: 222S-225S, 2005.

1 comment:

PastaQueen said...

I recently wrote a book and the bogus-ness of this stat was something I was going to bring up, but I too found the literature to be a mess and decided just not to address it. I'll be looking forward to your next post.