Thanks to reader Marie for the questions that spawned this blog. She asked:

I’m curious about the 95% figure. As far as I’ve read, that is based on some outdated and likely not valid research. I hope you understand I’m not attacking you, but it’s a statistic I see that you use often here and one that many of the nutritionists that I work with dispute. And I know I shouldn’t rely on anecdotal evidence, but I know several people personally (including myself) who have lost weight and kept it off. Now, the people who have kept it off have done it sensibly with healthy food and exercise. Others I’ve known who relied on more gimmicky approaches have regained. Here’s an article I’ve read. http://www.nytimes.com/1999/05/25/health/95-regain-lost-weight-or-do-they.html

Thanks for the thoughtful, non-attacking question Maria. Here is my answer.

First, my take on the article:

They say “…The true failure rate could be much better, or much worse, he said. ”The fact is that we just don’t know.”

They say that the number is based on a 1959 study conducted by Dr. Albert Stunkard and Mavis McLaren-Hume in which 95 of 100 participants failed. But then admit “Since the 1959 study, though, the statistic has been reinforced by most other clinical studies, which also showed people with discouraging results.” Studies like this one which is a 55 year study. They conclude that “Dieting has it’s own benefits…People who try to lose weight tend to eat better and exercise more, leading to increased fitness and lower blood pressure”. That, to me, is practically an endorsement of the Health at Every Size Paradigm since you can have the better eating and exercising without a side of failure and body shame.

At any rate, this statistic has a long history and was acknowledged at both the New Zealand Obesity Society conference in 2009 and again at the inaugural International Obesity Summit in 2010.

They are not questioning the 95% statistic based on any scientific study, but upon the anecdotal evidence of the National Weight Control Registry. This is a voluntary registry of dieters who have lost at least 30 pounds and maintained that for a year. The article claims that “Judging by their accounts, it is entirely possible for people without the resources to hire personal trainers and chefs to accomplish permanent weight loss.” And that’s where it goes off the rails for me.

According to their website:

There are currently more than five thousand members of the National Weight Control Registry, all of whom have lost significant amounts of weight and kept it off. These members lost the weight in a variety of ways and for a variety of reasons. Some have lost 30 pounds, some 130 pounds. Some have kept the weight off for one year, some for decades. What they all have in common, though, is a commitment to successful weight loss maintenance.

Ok, first of all, “more than 5,000”. Let’s say that they have 6,000 members, just to give them the benefit of the doubt. My research showed that between 45 million and 80 million Americans go on a diet every year. I’ll round down to 40 million just to be sure.. The registry started in 1994 and has 6,000 success stories. Using our extremely low estimate, since 1994, there were 660,000,000 attempts at dieting (including people who tried more than once). So if we are going to use the registry to prove weight loss success, it shows a failure rate of 99.991%. That’s not necessarily accurate of course because the registry relies on self-reporting. It’s possible that there are 32,994,000 people who successfully lost weight but didn’t report it to the registry. If that’s the case then the 95% failure rate holds true. If there are more than 32,994,000 who successfully lost weight but didn’t report it then the failure rate would be less. Or maybe when they said “more than 5,000” they actually meant 33 million.

As it stands, based on estimates that favor them: 660,000,000 diet attempts. 6,000 successes and 659,994,000 failures. What I’m trying to say here is that the registry is no help in proving the efficacy of dieting because it utterly lacks statistical significance and relies completely on self-reporting – in addition to under-reporting, some of those “success stories” could have regained their weight but not reported it. Also, the numbers are singularly unimpressive. Were I these two doctors, who make their living selling weight loss, I would not be waving these numbers around.

What these scientists are trying to say is that by studying the .009% of dieters who have succeeded they can find the secret to dieting successfully. That’s like studying Powerball winners to see the best way to become a hundred millionaire. On a side note, studies show that more than 50% of “overweight” people and more than 30% of “obese” people are metabolically healthy, but very few people seem to be studying us to see how they can make other overweight and obese people healthy. Why do we value .009% over 50% or 30%?

Maybe it’s because the Registry is run by two doctors who make their living selling weight loss and is predominantly funded by pharmaceutical and diet companies whose bottom lines depend upon people believing that they can lose weight. Conflict of interest? You decide.

Moving on. In order to talk about success or failure we first have to define them. Weight Watchers once claimed success when a study showed that participants lost around about 10 pounds in six months and kept off half of that for two years. Karren Miller-Kovach, chief scientific officer of Weight Watchers International at the time said: “It’s nice to see this validation of what we’ve been doing.”

Validation? Seriously? Lady, they lost 5 pounds in two years. I’m reasonably certain that I could lose 5 pounds in two years just by exfoliating semi-regularly. If Weight Watchers (or any weight loss company) was so successful then you probably wouldn’t be required to put “Results not typical” on every one of your ads, you know what I’m saying?

At any rate, to me success would have to be based on the diet industry’s own definition: Getting people into the “normal bmi” range. But that raises the question – if 95% of people who are 5 pounds over the “normal” range are “successful”, does it follow scientifically that 95% of people who are 200 pounds over would be successful by the same means? This is a trickier question than it sounds.

For me the bottom line is that even if a study did prove that some form of weight loss had success based on the diet industry’s definition, that would only be the start of the discussion. What are the risks? What happens to the people who don’t succeed? Are these people actually healthier, or are they just smaller? And for me the big question is “What’s the point”. I researched and chose Health at Every Size for a Reason. I already love my body and I’m healthy and Health at Every Size has given me everything I’ve ever wanted so I don’t need another path to health.

The reason I believe that diets fail 95% of the time is that there isn’t a single statistically significant study that shows otherwise. If you know of one, I’m open to reading it. (Note that I am not including weight loss surgery in this because when the side effects include death and lifelong misery, I think that’s a game changer.) The reason that I repeat the statistic here often is because I think that we’re being lied to. If your doctor told you that she was going to prescribe you a medicine that worked for Sally, but that she was legally required to say that Sally’s results weren’t typical, that you probably wouldn’t experience Sally’s results, and then told you that it was more likely to leave you less healthy than more healthy would you take it? If Viagra failed 95% of the time would we blame guys for not trying hard enough or would we say that the medicine didn’t work? It’s time to tell the truth: The Emperor has no weight loss. For more research on this subject, check out this post.