Weight Watchers Discusses That Biggest Loser Study

I posted a few week ago about that Biggest Loser study which talked about weight regain among Biggest Loser contestants.  Essentially the study found that out of a group of contestants studied several years after competing all but one had regained at least some weight.  And, in general, their resting metabolic rate (RMR) remained at a level much lower than would be expected by the size of the participant.  That is, they burned fewer calories than you expect using standard calculators to determine resting metabolic rate.

There was a New York Times story that talked about the study that I felt had been somewhat overhyped to assert that the study this meant that weight loss doesn’t work. Or rather, those who lose weight are doomed to regain.  In my post, though, I pointed out that many of the participants had regained some weight but had maintained significant weight loss.  While the reduced RMR found in the study participants is concerning, the study was also clear that the participants as a group had lost a lot of weight and maintained significant weight loss.

Now, Weight Watchers has weighed in with its interpretation of the study.  I have very mixed feelings about that article. While I do feel the article makes a number of valid points, I thought its treatment of the RMR question was simplistic at best and really didn’t come to grips with the key finding of the study — that weight reduced subjects years later had lower RMRs than would be expected based upon their size.

The Weight Watchers article points out that when you lose weight, of course, your daily calorie needs go down.  That is, after all, why your daily and weekly SmartPoints decrease as you lose weight (at least to the minimum).  The article also makes the point that if you regain some of your weight then your metabolism will increase and you will burn more calories.  In other words, if you lose 100 pounds and your RMR is now 1300 calories a day and then you gain 50 pounds,  your RMR won’t remain 1300 calories a day.

The Weight Watchers article also, quite rightly, points out that the Biggest Loser study has been misinterpreted by some as meaning that no can maintain weight loss.  That is, clearly, not true.  First, there are people who lose weight and maintain all of their weight loss.  While this may not be a common result, it is a possible result. Weight Watchers points out in the article that many members of the National Weight Control Registry lose and maintain weight loss.  I also certainly know a number of long-term lifetime members of Weight Watchers who have maintained weight loss for years.  So, yes, losing and maintaining weight loss is possible.  It just isn’t always easy.

Another major point is that losing a substantial amount of weight and then regaining some of it doesn’t make you a failure.  Many people lose significant weight, and regain some of it, but remain far below their high weight.  To simply dismiss that as “they regained their weight” is misleading.  I think Weight Watchers clearly understands that significant weight loss is important even if there is some regain. I can use myself as an example. When I first joined Weight Watchers in 1988, I weighed about 168 pounds.  My goal weight was 125 pounds and my lowest recorded weight after getting to goal was 119 pounds.  I am now at a normal BMI with an official goal weight of 146 pounds.   My lowest weight since getting to goal has been 142.8 pounds for a total loss of 64.6 pounds from my high weight of 207.4 pounds (yes, after getting to 119 pounds I regained it all and more).

So, am I a failure?  After all, I once had a weight goal of 125 pounds and weighed 119 pounds. I am not at that goal and have no real plans to ever be at it.  (It could happen, but it isn’t my goal).  So, if  ever weighing more than your lowest weight means you are a regained failure, then I am a miserable.  But, I’m not a failure because I now weigh more than I weighed then. 146 pounds is a maintainable weight for me and is within a healthy weight range for me.  I’ve lost 30% or so of my high weight.  Am I a failure because I once weighed even less than that?  I think not.

Let’s say that I had found that I could maintain a weight of 155 pounds, which is in the overweight category.  Would that mean I was a failure because I couldn’t get to a normal weight range?  No, it wouldn’t.  I would have lost over 50 pounds and would be far better off than I had been at 207 pounds.

And, so it is for many of the Biggest Loser contestants who are considered by some to now be failures because they regained some weight.  In many instances, they still maintain significant weight loss.  That is not failure. So, I think the Weight Watchers article was very good in debunking the notion that people can’t maintain weight loss.

I am less happy, however, with how Weight Watchers treated the topic of metabolic adaptation after weight loss. The article says that the Biggest Loser study was been misinterpreted as evidence that “Weight loss can lead to permanent damage to your metabolism (RMR and daily calorie needs).” I think that statement goes a bit too far.  Personally, while not an obesity expert, I have read enough articles on this issue to realize that the verdict is still out as to whether a person who has lost weight will have “permanent damage” to RMR and/or daily calorie needs.  I certainly don’t think the Biggest Loser study is dispositive on this point.  It doesn’t prove that such permanent damage exists. But, it is still evidence that suggests that this issue really needs to be looked at.

Weight Watchers points out that the Biggest Loser study is a small study involving people who lost a large amount of weight very quickly and not in a typical way.  That is certainly a valid point. So, yes, I agree that the results of the study may not be generalizable to the entire universe of people who lose weight.  But, the discussion shouldn’t really stop there. The Biggest Loser study points out that studies have failed to support the idea that rapid weight loss increases the risk of weight regain.  Now, it is possible that those studies aren’t applicable to the Biggest Loser situation because that weight loss is especially rapid and uses methods of weight loss that are not very typical.  So, it is fair to point out that the Biggest Loser study may not apply to everyone who loses weight.

But, I felt the Weight Watchers article failed to discuss research that has found losses on energy expenditure after weight loss beyond the losses you expect due to lower body weight.  For example, the Biggest Loser study cited a meta-analysis which found that people who had lost weight showed a 3% to 5% lower RMR compared to control subjects who had not lost weight.  The Weight Watchers article criticizes the Biggest Loser study for being small and perhaps not applicable to everyone.  Fair enough.  But, I felt the article should have discussed the other studies that have found RMR decreasing in people who have lost weight beyond what would be expected due to weight loss.

Again, I don’t really think there is dispute that if you lose weight your RMR will go down and if you gain weight it will go up.  That is not the issue.  The question is whether your RMR goes down more for the person who lost weight than for the person who didn’t lose weight.  That is, if there are two people of identical size and body composition and one of them has an RMR of 1120 and the other has an RMR of 1224 why is that?  Now some of it may be genetics.  People vary in their RMR for a lot of reasons.  Now, imagine that you do a study and find out that most people of that size have an RMR of 1224.  But, then you find a group of people of the same size and they have an RMR of about 100 calories a day less.  Maybe you then find out that all those people with the lower RMRs were once obese and lost weight.  Maybe the fact that they were obese and went on calorie restricted diets is why they now have lower RMRs.  But, maybe the causation goes the other way.  That is, maybe these people always had lower RMRs and that was part of why they became obese in the first place.

So, figuring out why the weight reduced people and those who were never overweight have lower RMRs is an interesting question.  And, maybe you find out that this effect lasts only a short period of time (but the Biggest Loser study found it existed 6 years later).  And, if so, then maybe you want to find out why sometimes this effect doesn’t occur or it lasts only a short time or it lasts a long time.

And, that is why sometimes science doesn’t us nice neat little answers.  It isn’t enough to just dismiss the Biggest Loser study because of the unusual nature of the weight loss of the participants.  It is particular not enough to dismiss when a bunch of other studies have found some degree of lower RMR in weight reduced subjects as compared to people who didn’t lose weight.  But, the Weight Watchers article doesn’t really get into any of that at all.

But, this is a complicated issue.  Another reason it is complicated is that some studies have found that there is less energy expenditures in weight reduced people, but that the RMR isn’t the difference.  The difference is in the other components of energy expenditure (basically, the components are RMR, energy used to burn the food we eat, energy burned in exercise, and energy burned in non-exercise activity).

Years ago, I read a 1995 study in the New England Journal of Medicine that is quite well known called “Changes in Energy Expenditure Resulting from Altered Body Weight.I’ll call this the “Leibel Study” based upon the lead author being Rudolph L. Leibel, a well known researcher. The key finding was:

Maintenance of a body weight at a level 10 percent or more below the initial weight was associated with a mean (±SD) reduction in total energy expenditure of 6±3 kcal per kilogram of fat-free mass per day in the subjects who had never been obese (P<0.001) and 8±5 kcal per kilogram per day in the obese subjects (P<0.001). Resting energy expenditure and nonresting energy expenditure each decreased 3 to 4 kcal per kilogram of fat-free mass per day in both groups of subjects. Maintenance of body weight at a level 10 percent above the usual weight was associated with an increase in total energy expenditure of 9±7 kcal per kilogram of fat-free mass per day in the subjects who had never been obese (P<0.001) and 8±4 kcal per kilogram per day in the obese subjects (P<0.001). T

Those who lost weight who had been obese did burn fewer calories than would be expected by their body composition, but the reason for this metabolic adaptation is not entirely clear. The authors noted:

Our results have immediate implications for the clinical management of obesity. Many obese people who lose weight have metabolic alterations similar to those observed in our subjects. The reduction in energy expenditure to a level 15 percent below that predicted for body composition, as a result of a 10 percent (or larger) decrease in body weight, is large when one considers that an average daily intake of 2500 kcal would be associated with a positive energy balance of approximately 375 kcal per day. In addition, the sense of hunger or dysphoria that may accompany this state of reduced energy expenditure will promote increased food intake, further widening the gap between energy output and intake.

I have been interested in this subject for years as I have read some people make various arguments. Some argue that weight reduced people simply do not maintain a reduced energy expenditure forever. Some argue that there is a reduced metabolic rate after weight loss and it is due to a change in RMR that occurs after weight reduction.  The cause of the lower than expected RMR that some studies find with people who have lost weight is not clear.  Perhaps, the people started with a lower RMR and that played a factor in becoming obese.  Or, perhaps, losing weight itself somehow impairs RMR.   Others argue that the change in expenditure for weight reduced people is a change in non-RMR energy expenditure.  That is, that weight reduced people simple move less after losing weight than people who were never overweight and this is why they burn fewer calories.

I pointed out awhile ago that the calories burned during non-exercise activity can have a powerful effect on total calories burned.  It may be that some people who were once obese tend to be less active (for whatever reason) and may burn fewer calories than others their size who were never inactive.  And, even after weight reduction, they continue to burn fewer calories. Or, maybe not.  Maybe RMR really is lower in at least some people who have lost weight.

At this point, I think the jury is still out on these questions.  As far as I can tell, research on this is ongoing and there final answers are not yet clear. For me personally, I know that my RMR soon after I got to my goal weight of 146 was less than was expected based upon my size.  I actually paid $75 to get this measured in a lab, not just estimated using a calculator.  I knew of the debate on this issue and decided that I wanted to actual know how my RMR measured up to what would be expected using a standard calculator. I found that my RMR was 1120 calories per day. The Mifflin St Jeor formula (the formula Fitbit uses) at the time would have predicted my RMR to be 1224 calories.  Now, I am skinny fat and felt my high body fat could have been the reason for the difference.  The Mifflin St Jeor formula is based upon size and not body fat. So I also calculated my expected RMR using the Katch McArdle formula which uses body fat percentage and not just weight to calculate RMR.  I knew my body fat because I paid $50 to have it tested in a Bod Pod.  Using that formula, my RMR would have been 1163.  That is pretty close to 1120, but still not as low.  So, for me, for whatever reason I know my RMR is less than would be expected by RMR calculators for someone of my size and body composition. Note, I am not saying that this is due to my weight loss.  Maybe I was just born with a lower RMR than most people.  Maybe that it is part of why I became overweight.  But, that is information I don’t know. But, I know I can’t just rely on standard RMR calculators to tell me how many calories I can eat.  For whatever reason, my RMR is lower than most people of my size and body composition.

I also know that my non-RMR calorie burn is without doubt less than that of most people my size.  I tend to be sedentary.  It isn’t so much laziness, as what I like to do.  I like to read articles about RMR and to write posts like these.  I can easily spend hours on the computer simply going from one interesting article to another.  When I was a kid I sometimes read the encyclopedia for fun.  I haven’t changed.  I like to acquire knowledge and love sitting at a computer to do it.  Of course, I like other things too.  But, many of those also avoid sitting.  Playing World of Warcraft or Hearthstone may be fun, but I don’t burn a lot of calories doing them.  And, I worked full time for over 30 years at a desk job.  I didn’t do a lot of walking except from the parking garage to my office.  Going down the hall to visit a colleague didn’t burn a lot of calories either.  So, maybe those things have something to do with why I gained weight in the first place and have something to do with why I burn fewer calories than some people my size who were never overweight.  And, maybe I tend to fidget less than other and my movement is lower than most so my NEAT (non-exercise activity thermogenesis) is lower than others my size.  So, this is all really complicated.

And, this is why I think the Weight Watchers article begs the question on the metabolism issue. Weight Watchers makes a big point in the article of saying that if you regain some weight you will burn more calories.  I don’t disagree.  I’m kind of not thinking that is a big issue. In fact, Weight Watchers point on this is a classic example of a straw man argument.

I’m sure that if I regained 50 pounds my RMR wouldn’t be 1120 any more.  It would go up. But — that isn’t the question.  Weight Watchers does a good job in the article of making the point that our RMR and daily calories burned will go up if we gain weight.  But, that isn’t the question. The question that the Weight Watchers article didn’t clearly answer is whether someone who loses weight will permanently burn fewer calories than would a person of similar size/body composition who didn’t lose weight.

The most frustating part of the Weight Watchers article is this passage:

A great example of this is a study published in the New England Journal of Medicine in 1995, which measured the RMRs in 41 people as they lost and gained 10 percent of their body weight. The study found that daily calorie needs responded to change in weight, in both directions. For example, a 10 percent weight loss corresponded, on average, with a 9 percent decrease in daily calorie needs, and a 10 percent weight gain corresponded with a 14 percent increase in daily calorie needs. In addition, the study measured eight women at their initial weight, and again as they gained 10 percent, and then lost 10 percent of their body weight, and finally when they returned to their starting weight. There was no significant difference in the energy needs of the women at their initial weight or when they returned to that weight. In other words, there is no permanent “damage” to metabolic rate—just an increase when weight is gained and a decrease when weight is lost.

This passes tried to use that 1995 study to try to make the argument that there is no permanent damage to metabolism from losing weight.  There are three big problems with the discussion above. First, the passage above doesn’t discuss whether these 41 people were people who were or had been obese or whether they were people who had ever tried to lose weight before. There simply isn’t enough information given about the participants or the study design to support the conclusion reached.  The discussion  mostly makes the same point made before – if you lose weight you burn fewer calories and if you gain weight you burn more calories.  They do argue that there is no permanent damage to metabolic rate because 8 women were studied at their initial weight, gained 10 percent, then lost percent and returned to their starting weight and there was no significant difference in their energy needs from the point when they started to when they returned to their starting weight. That is certainly a valid point to bring up.

But, that also reveals a second flaw.  Weight Watchers dismissed the Biggest Loser study because it involved 14 participants.  Now it is arguing there is no permanent damage to metabolism because of findings involving 8 women.  You can’t have it both ways.  If 14 participants are small enough to invalidate a study, then 8 participants are very persuasive.

The biggest flaw, however, in the discussion of the 1995 study is that there is no citation to the actual study.  I don’t put a lot of faith in citations to unnamed studies.  When I discuss a study at any length I do my best to cite to the actual study if available or to at least to some external source about the study.  I want to read the study and find out about the methodology and the results and find out what the authors thought it all meant.  So, when I read the passage above, I went to the Weight Watchers expert chat and had an extended discussion with a nice person who tried to find a citation to the study.  He was unable to do so.  He said he had no resources other than what was in the article itself.

As it turns out, I suspect that study Weight Watchers is taking about is the 1995 Leibel Study I cited to above.  Part of how Weight Watchers described the study is as follows:

A great example of this is a study published in the New England Journal of Medicine in 1995, which measured the RMRs in 41 people as they lost and gained 10 percent of their body weight. The study found that daily calorie needs responded to change in weight, in both directions. For example, a 10 percent weight loss corresponded, on average, with a 9 percent decrease in daily calorie needs, and a 10 percent weight gain corresponded with a 14 percent increase in daily calorie needs.

Why do I think Weight Watchers is talking about the Leibel Study?  Well, the Leibel study involved 18 obese subjects and 23 subjects who had never been obese.  That is, it involved 41 people. Part of what was measured was RMR, but the study also measured total energy expenditure, nonresting energy expenditure and the thermic effect of feeding.  The study indicates that the subjects were studied at their usual body weight and after losing 10 to 20 percent of their body weight or by gaining 10 percent of their bodyweight.  This sounds an awful lot like the participants in the study referred to by Weight Watchers doesn’t it.

The Weight Watchers employee who couldn’t identify the study in the Weight Watchers article did direct me to the archive for the 1995 New England Journal of Medicine. I wasn’t going to go through issue one by one but I did do a search for obesity articles in 1995 and scanned over the list of subjects.  The Leibel Study seemed to be the only applicable one.  I told the Weight Watchers employee that I suspected the Leibel Study was the one cited in the Weight Watchers article.  He said he had been trying to scan through the 1995 articles himself and he thought it might be as well, but he hadn’t wanted to say so since he wasn’t sure.

So, based upon Weight Watchers description of the study in its article I think Weight Watchers was talking about the Leibel Study.  If not, I certainly welcome a correction.  If that is the study that Weight Watchers was talking about, I feel the description of it largely misses the point of the Leibel study.  Weight Watchers basically groups together the obese and never obese people.  But, the Leibel study separates them out.  And, while Weight Watchers concludes from the study that there was no permanent damage to metabolism, the actual study makes it clear that there are differences in metabolism between those who were obese and those who hadn’t been.  As mentioned above, the authors cautioned:

Our results have immediate implications for the clinical management of obesity. Many obese people who lose weight have metabolic alterations similar to those observed in our subjects. The reduction in energy expenditure to a level 15 percent below that predicted for body composition, as a result of a 10 percent (or larger) decrease in body weight, is large when one considers that an average daily intake of 2500 kcal would be associated with a positive energy balance of approximately 375 kcal per day. In addition, the sense of hunger or dysphoria that may accompany this state of reduced energy expenditure will promote increased food intake, further widening the gap between energy output and intake.

And, they went on to say:

Physicians should be aware that for some obese patients the achievement of what is considered to be a more helpful body weight may be accompanied by metabolic alterations that make it more difficult to maintain the lower weight.

While this may be discouraging, that is what the authors of the Leibel Study thought was important in their discussion of the results.  It is not nearly so rosy as what Weight Watchers argues in its article.  In fact, it hard to square that conclusion with Weight Watchers saying there is no permanent damage to metabolism from losing weight.  Note carefully:  I am not saying that there is a permanent damage to metabolism from losing weight.  Maybe the effect isn’t permanent.  Maybe the lower metabolism existed before the obesity occurred.  Maybe there are other explanation.  I am not confident that science can yet answer that question.

I just don’t feel that Weight Watchers really proved that people who lose weight don’t have a change (either permanently or long-term) in their metabolism after weight loss.  Why does this even matter? Well, if you get to your goal weight and look at typical calculators of energy expenditure you may think you can maintain your weight eating an amount that will cause you regain.  For me, it has been important to know that my RMR is lower than expected for someone my size and to consider my level of activity so that I eat an amount that is appropriate for my metabolism.  I don’t feel I can compare myself to the person who weighs 145 pounds who was never overweight.  So, it is important for me to know that.

I think it sends a “feel good” message to tell me that if I gain weight my metabolism will burn more calories, but that doesn’t do much to tell me whether I (a weight reduced person) am burning fewer calories at 145 pounds than I would be burning at 145 pounds had never gained and then lost weight.

Maybe that “feel good” message gives a lot of hope to some people and encourages them to lose weight.  Maybe if they feared that losing weight “damaged” their metabolism they wouldn’t try hard to lose weight.  Maybe if they knew maintenance was hard they would feel discouraged.  But, reality is reality.  Maintenance is hard and constant vigilance is needed for many people. Pretending it away doesn’t help.

I appreciate that Weight Watchers wrote an article making it clear that long term weight loss is possible.  And, that Biggest Loser study doesn’t change that fact. I just wish they hadn’t over-simplified the discussion of whether people who have lost weight burn fewer calories than would be expected for their size.

 

 

Comments

  1. Darlene says

    This is a very in-depth analysis – thanks for sharing the WW link as I hadn’t seen it. My highest weight was 258 pounds, today I weigh 148 pounds. I joined WW (for the second or third time) in 2001 at 245 and got to goal (140) in 2002. I regained about 60 pounds and lost it again (changed my goal to 150 and got to 147 in 2009). I have been between 138-153 since then. So I’m an example that it can be done, but no, it is not easy. Maintaining weight loss requires a lot of mental energy. I had my RMR done after reaching goal the first time – it was just under 1400 calories a day – I guess I was lucky compared to your number! I was able to maintain on about 40 points a day for several years when I was exercising 10-12 hours a week. I can’t do that anymore so I hope I can continue to maintain and not have to eat a lot less food! I would be interested to see what my RMR is now. PS you are looking great and I hope your recovery continues to go well.

    • says

      Thanks. Testing for RMR after goal is I think a good thing, there are so many factors in it. I have been working on improving body composition and I’m doing some body contouring surgery so after I’m done with that and feel I am “done”, I may test again. I am just one of those people that likes to know the data to help me figure out the best course of action.

      Recovery is going well, thanks.
      Kitty recently posted…Weight Watchers Discusses That Biggest Loser StudyMy Profile

  2. JIm says

    ” I just wish they hadn’t over-simplified the discussion of whether people who have lost weight burn fewer calories than would be expected for their size”

    Nice cogent and thoughtful analysis, I agree. (I am a physician by training.)

    (I particularly enjoy your ability to parse the obesity medical and scientific articles, and make them relevant.)

    It certainly looks like there is “something” ( less movement?, the cause is still unclear) that results in fewer calories for RMR then expected or predicted after one loses a significant amount of weight.

    Doesn’t mean one can’t be successful with weight maintenance- but one has to be more vigilant.

    For myself, I’ve lost 75 pounds with WW over the past 18 months, reached a 24 BMI, and made “lifetime”.

    But, as everyone knows, the real battle then begins- maintenance. 😉

    Walking/jogging five miles/day, tracking foods, weighing daily, weighing weekly at WW meetings, attending WW for inspiration weekly- yes, I’ve managed so far- 7 months.

    • says

      Thanks for the comments. One of the actual reasons I started this blog was that I got so frustrated with how articles about studies were discussed and over-simplified.

      And, yes, I think that weight loss maintenance really does require ongoing vigilance. It is possible but requires just as much effort as losing weight did.
      Kitty recently posted…Weight Watchers Discusses That Biggest Loser StudyMy Profile

  3. Stacey says

    I really enjoy these types of posts, you have a gift for analyzing scientific studies and paraphrasing them into the vernacular. I stumbled upon your blog after doing a Google search and have read all of the back entries 🙂

    I’m glad you saw WeightWatcher’s response to the Biggest Loser study – I read it a few days ago and though it was a bit too full of butterflies and rainbows and a bit light on reality. I’m all for encouragement, but not at the expense of honesty and truth.

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