Weight Regain and Metabolic Adaptation
The New York Times recently had an article about weight regain among many people who lost weight on The Biggest Loser. The article is depressing at first glance, but was no surprise to me. The big takeaway from the article is that, after losing weight, people burn less calories than would be expected by the person’s size. This was based upon a study of Biggest Loser competitors. For example, Danny Cahill originally weighed 430 pounds. At the finale, he weighed 191 pounds and he now weighs 295 pounds. The article indicates that he now burns 800 fewer calories a day than would be expected for a man his size! And, this is shown over and over again in the examples given in the article. There are a couple of nice graphs in the article. One shows that out of 14 contestants studied, 13 have regained at least some of the weight lost in the 6 years since the competition. Only one contestant has lost weight. And, another graph shows that nearly all of the contestants have slower metabolisms and burn fewer calories than would be expected. The study has received a lot of attention in the blogosphere. A few of those articles are here, here, here, here, here, and here.
It can be depressing to read the article and the study and to see how much weight has been regained and to see that the resting metabolic rate of those studied is so much lower than would be expected based upon their size. And, this is true 6 years after the weight was lost. The metabolic adaptation (i.e. burning fewer calories than expected) continues for a long time. It is easy to read this and feel that weight loss maintenance is hopeless.
The study makes the point that resting metabolic rate, 6 years after the competition was over, “remained suppressed at the same average level as at the end of the weight loss competition. Mean RMR after 6 years was ~500 kcal/day lower than expected based on the measured body composition changes and the increased age of the subjects.” That really is sobering to read.
However, this was not a surprising finding to me. Years ago, I had read similar findings, such as in this 1995 study finding that weight reduced subjects burned fewer calories than would be expected after weight loss. So, this idea that metabolism remains slowed after losing weight even while on maintenance is not new. It can be depressing to think of this as it really does show why it can be hard to maintain weight loss. The point being that, even years after having lost weight, the body continues to burn fewer calories than the same size body would be expected to burn if the person had never been overweight. And, as can be seen from The Biggest Loser study this persists for years (6 years in the study). In fact, I am resigned to the fact that it may be permanent. The idea that the person who weighs 150 pounds who used to weigh 250 pounds burns fewer calories than the person who always weighed 150 pounds can seem unfair.
That does not, however, change the reality. I can see the metabolic adaptation in my own body. I actually had my resting metabolic rate tested last fall. And, I burn fewer calories than would be expected based upon my age and size. My RMR (what I burn at rest without really doing anything else) was 1120 calories a day. The Mifflin-St Jeor formula that Fitbit uses, for example, would have expected me to have an RMR of 1224. So, the calorie burn information I was getting from Fitbit was too high because it was based upon an RMR that was about 100 calories a day too high. It is upsetting to realize that I don’t burn as many calories as might be expected just based upon size and age. But, again, that unfairness doesn’t change my reality. And, I have to pay attention to this. On days that I don’t exercise I burn under 1400 calories. In fact, if I am totally sedentary (which I don’t recommend), I burn under 1300 calories in a day. Even on days that I am active, I rarely burn more than 1600 calories.
On Fitbit, I manipulated my height, until I got a RMR that was close to my actual RMR of 1120 calories. So, I think my Fitbit calorie burn now is more accurate. Assuming so, in March of this year I burned only an average of 1395 calories a day. And, I did 219 minutes a week of cardio exercise as well as an average or 17 minutes a week of strength training (I had a shoulder injury that month so had to miss several weeks of strength training). If I had been eating 1500 calories a day, I would have gained weight. The reality is that after losing weight, if I want to maintain, I still can’t eat all the points that Weight Watchers tells me I can eat on maintenance. That is metabolic adaptation in action. So, yes, the metabolic adaptation can result in weight regain if you eat as if you didn’t have that reduced calorie burn effect. But, if you know it is there then you can prepare for it in terms of how much you eat or how many extra calories you try to burn.
Yes, it is discouraging to read the article and see so many people having regained weight. But, I think most of the angst is based upon all or nothing thinking. For example, while it is true that only 1 of the 14 contestants studied weighs less now than when the competition ended, it is also true that many of the contestants maintained a significant amount of lost weight. The study notes that 57% of the participants did maintain an at least 10% weight loss. That is actually pretty impressive given that this is a 6 year follow up. While Cahill regained about 100 pounds, for example, the fact is he has also maintained a 30% or so weight loss which is super impressive.
I read some comments on the New York Times article which implies that the reason for the regain is because of losing weight very quickly. The study itself debunks this argument citing research studies that found that weight loss rate alone does not affect the long-term weight regain. That does not mean that I approve of the whole Biggest Loser concept. I don’t watch that show because I don’t think that kind of weight loss method is realistic and I think it leads people to have unrealistic expectations in terms of how much weight can be lost in a given period.
I have long felt that one of the reasons for weight regain was that people who had lost a lot of weight were burning much fewer calories than they thought and that to maintain weight loss it was difficult to stick to the low number of calories that they could eat to maintain weight loss. And, in my opinion, far too many people lose weight and then regain some amount of weight and feel like failures even though they have maintained a large weight loss. And, feeling like they failed for not staying at a “normal” BMI, they sometimes give up and regain everything. I am a big believer in picking a goal weight based upon what is sustainable. And, for me, part of knowing what is sustainable is recognizing that I don’t burn the same number of calories someone my weight would burn according to the formulas out there because those formulas assume that someone who lost weight burns the same calories as someone of the same weight who was never overweight. And, of course, knowing this is one reason that I try to burn more calories through exercise. That extra couple of hundred calories each day makes a big difference. It makes maintenance possible instead of utterly impossible.
The New York Times does also have a nice follow up article that talks about what to do to try to maintain weight loss. The article talks about people who successfully maintain often talk about being vigilant all the time, keeping close track of weight, controlling what is eaten (including by weighing and measuring), often exercising and resisting cravings and hunger. As I read that, I kept thinking that those are mostly things that are really consistent with continuing to follow Weight Watchers on maintenance. This is the reason that I still track what I eat, I weigh and measure food (just as I did for dinner tonight), I keep track of my FitPoints and I weigh almost daily.
Just a brief pre-surgery update. Eating has gone well this week and I am back on track. I did eat a lot at my son’s birthday dinner, but I was prepared for it. If I weighed in today, I would have been within my Weight Watchers goal range. I have completed all my shopping to get ready for surgery. Today, I decided to replace all of my makeup before surgery. I tend to not wear a lot of makeup so I keep it for longer than is usually recommended. I don’t want to take a risk of getting an infection after surgery, though, so decided to just replace everything. Here is a pic with the new makeup on. It is a little heavier than I like it (it was done at the store, not by me), but I thought the colors looked good. I can perhaps use this as a “before” picture later on. I have some without makeup but it is good to have a few with makeup on.