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I was reading this article on Cracked which claims:

The number of people who go from fat to thin, and stay there, statistically rounds down to zero.

That seemed like a pretty incredible claim, considering the sheer amount of diets and such available to help people lose weight (and keep it off, ostensibly).

How reliable are these claims? If I am fat, am I doomed to always be that way despite my best efforts?

  • What kind of "official" did you have in mind? – dmckee May 24 '14 at 2:06
  • I used the word "official" in the title, because that's what the article said. I am not looking for anything specifically. – Ash May 24 '14 at 2:20
  • H'rumph. It's a filler word with no semantic content. – dmckee May 24 '14 at 2:31
  • I figured it was one of those hyperbolic things, like Upworthy titles. I can remove it, if you think it is unecessary. – Ash May 24 '14 at 3:03
  • 3
    Thanks. Maybe it is a sign that I am getting old, but that kind of thing bugs me more these days. – dmckee May 24 '14 at 3:05
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Disclaimer: I practice Health At Every Size myself, which is why I have these studies on hand.

Mann and Tomiyama performed a review of studies on weight loss:

These studies show that one third to two thirds of dieters regain more weight than they lost on their diets, and these studies likely underestimate the extent to which dieting is counterproductive because of several methodological problems, all of which bias the studies toward showing successful weight loss maintenance. In addition, the studies do not provide consistent evidence that dieting results in significant health improvements, regardless of weight change. In sum, there is little support for the notion that diets lead to lasting weight loss or health benefits.

The Heritage Foundation found that the results of exercised-based interventions were small as well:

A short-term exercise intervention can induce favorable changes in body composition, but the magnitude of these changes is of limited biological significance.

Some idea of their definition of small but significant:

There were significant decreases in all measures of fat distribution for the total sample, although the magnitude of the change was generally small. The largest change was in the abdominal visceral adipose tissue (5.9%) and the smallest change was in the waist-hip ratio (0.6%). When analyzed by group, blacks showed no changes in hip circumference or waist-hip ratio. Men had a greater change than did women in abdominal visceral fat, and white women had a greater change (1.2 mm) than black women (0.3 mm) in waist circumference.

1.2mm of waist size is hardly the dramatic change promised in most weight loss ads! This table from their study shows less than half a kilogram of weight loss overall.

Miller WC found:

A brief survey of the most popular dieting techniques used over the past 40 yr shows that most techniques cycle in and out of popularity and that many of these techniques may be hazardous to health. Data from the scientific community indicate that a 15-wk diet or diet plus exercise program produces a weight loss of about 11 kg with a 60-80% maintenance after 1 yr. Although long-term follow-up data are meager, the data that do exist suggest almost complete relapse after 3-5 yr.

Bacon and Aphramor, in a study evaluating traditional weight loss techniques vs body-positive plans such as Health At Every Size, noted:

Evidence: Long-term follow-up studies document that the majority of individuals regain virtually all of the weight that was lost during treatment, regardless of whether they maintain their diet or exercise program [5,27]. Consider the Women's Health Initiative, the largest and longest randomized, controlled dietary intervention clinical trial, designed to test the current recommendations. More than 20,000 women maintained a low-fat diet, reportedly reducing their calorie intake by an average of 360 calories per day [102] and significantly increasing their activity [103]. After almost eight years on this diet, there was almost no change in weight from starting point (a loss of 0.1 kg), and average waist circumference, which is a measure of abdominal fat, had increased (0.3 cm) [102].

Finally, the National Weight Control Registry defines a "successful" diet as one that produces > 30lbs weight loss. Their numbers are vague, but at best .02% of diets are "successful". An analysis of their numbers can be found here, and you can find what data they have chosen to make public here.

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I would place these claims inaccurate, due to improper representation of the study that the Cracked article itself supplied.

http://ajcn.nutrition.org/content/74/5/579.full Conclusion: "Five years after completing structured weight-loss programs, the average individual maintained a weight loss of >3 kg and a reduced weight of >3% of initial body weight. After VLEDs or weight loss of ≥20 kg, individuals maintained significantly more weight loss than after HBDs or weight losses of <10 kg."

While the >3 kg, which with a conversion of ~2.2lbs/1kg comes to roughly >6.6lbs does not seem substantial (although it is far from the "rounds to zero" that the Cracked article claims in its header), it is important to note two points from the article. Under "Study Identification," the article states " Follow-up values were assessed at 1, 2, 3, 4, and 5 y." Under "Meta-Analysis," it states that "Weight-loss maintanance(kg)=initial body weight-bodyweight at follow up. As defined by the article, the ">3kg" refers not to the entirety of weight loss throughout the trial, but instead to the weight loss observed at the annual follow-up (overall averaged out). This is further exemplified by this table, which more clearly lays out the parameters of the conclusions of the trial - http://ajcn.nutrition.org/content/74/5/579/T2.expansion.html, and a graph which shows the long-term weight loss maintanance http://ajcn.nutrition.org/content/74/5/579/F1.expansion.html .

Given that they represented this study so greatly, and the other study was not a study focusing on individual trials, but instead on methodology for weight loss and the reasons for its importance, I believe it is fair to say that the other claims made in the article are unsubstantiated.

As for the second question, there is currently a great amount of evidence to indicate that weight loss programs can be successful. When reading these studies, it is important to remember that averages are, ultimately, averages, and due to many modern clinical trials following intent to treat analysis (a method in statistics that retains "bad" or failed results in order to be more statistically true to the data, as well as be more representative of real world situations) the weight loss will likely be higher for those dutifully following the parameters of the trial, which can be demonstrated this through a 2011 study published in the New England Journal of Medicine (http://www.nejm.org/doi/full/10.1056/Nejmoa1108660#t=articleResults)

In this trial, which focused on comparing the effects of two monitored weight loss programs versus a third with no intervention, the following results were found: "At 6 months, the mean (±SE) adjusted change in weight from baseline was −1.4±0.4 kg in the control group, −6.1±0.5 kg in the group receiving remote support only, and −5.8±0.6 kg in the group receiving in-person support. t 24 months, the mean change in weight from baseline was −0.8±0.6 kg in the control group, −4.6±0.7 kg in the group receiving remote support only, and −5.1±0.8 kg in the group receiving in-person support." This is slightly more optimistic, but what is more indicative of the potential benefits are in Table 3. (http://www.nejm.org/doi/full/10.1056/Nejmoa1108660#t=articleResults) . At 6 mo and 24 mo, statistical significance was found for obtaining a BMI <30 when utilizing both support and remote. As the NIH identifies obesity as a BMI equal to or greater than 30, this means that there was a significant effect of monitored, dedicated weight loss therapy on helping individuals overcome obesity in a trial extending for two years. This implies that there is a great deal of optimism in terms of overcoming weight problems, if one is capable of following a more rigid regimen with the aid of an external, motivating source such as those demonstrated in the trial.

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