There was an interesting study recently published that talked about what happens after weight loss. It is easy while losing weight to think about the “end” as being when we get to goal weight. There is that assumption that if we can just get there, then we can stay there. Especially if it has been so hard to lose weight, it seems that we will never gain weight again. How often did I say to myself that “I will never let myself get fat again.” And, yet, I did.
There are many theories as to why that happens. Maybe it is genetics. Maybe it is metabolic adaptation – the body burning fewer calories than would be expected after weight loss. Maybe it is just that I am a flawed person who lacks self control and discipline. No, I don’t actually think that the last one is right. But, all too many people do still think that and they tend to think weight loss and maintaining it is easy.
I posted awhile back about the recent Biggest Loser study which talked about metabolic adaptation. And I posted about Weight Watchers response to that study. I did feel that study and other research I’ve read on the subject makes a good case that people who have lost weight typically burn fewer calories than people of similar size and characteristics who were never overweight.
But, I also felt that that probably doesn’t explain all of the reasons that most people do not maintain weight loss. Regardless of how people lose weight, the pattern of weight loss and regain is fairly typical. A recent article in the Lancet entitled “Weight loss diet studies: we need help not hype” by Yoni Freedhoff and Kevin Hall (Hall is one of the authors of the Biggest Loser study) points out the problem:
One insight that can be gleaned from the existing weight loss literature is that even the most divergent of diets seem capable of affecting a degree of short-term success, with some diets perhaps leading to marginally greater losses than others over periods of several months.1 But since obesity is a chronic condition, it is the long term that matters. An effective diet for clinical weight management needs to be established over time scales of years to decades. Studies that have lasted 1 year or more typically do not show significant differences between prescribed diets, much less any clinically meaningful differences in maintenance of lost weight.
And, they show a graph that shows a typical pattern for weight loss. That is a sharp decrease in weight after beginning a diet, then weight being regained eventually leveling off close to the original weight. Over the years I’ve read a lot of diet studies and I’ve seen similar graphs many times. In weight loss studies, it always seems to be the same. Every diet seems to work for initial weight loss. Then, weight regain starts and most of the lost weight is regained. Often, there is some amount of overall loss that remains but it is relatively small. This seems to always happen, regardless of type of diet.
This is one reason I’ve felt that for weight loss itself there is no one magic way of losing weight. All diets work and no diets works That is, if you have a calorie deficit you can lose weight on any diet (or weight loss plan). But, some amount of regaining happens for most people regardless of diet or food plan.
Again, the issue is why. As mentioned, I do think metabolic adaptation is part of it. In a recent study entitles “How Strongly Does Appetite Counter Weight Loss? Quantification of the Feedback Control of Human Energy Intake” however, the authors (who include the same Kevin Hall mentioned above) also found another potential culprit. In short, they found that the more weight that was lost by their subjects, the greater their appetite increased:
In summary, our results provide the first quantification of the energy intake feedback control system in free-living humans. We found that appetite increased by ∼100 kcal/day above baseline per kilogram of lost weight—an effect several-fold larger than the corresponding energy expenditure adaptations.
That is, the largest effect came from increased appetite, not from metabolic adaptation (that did play a factor). I have linked to the actual study above, but here is a link and another link to articles about the study. Basically the idea is that when we lose weight, the body defends against it by increasing our appetite so that we eat more. And, as we eat more we regain.
Now, I will say that the study caused me to raise my eyebrows when it said that appetite increases by 100 calories a day above baseline per kilogram of lost weight. That would be almost 30 kilograms for me so that would be an extra 3000 calories a day. The fact is that I’m not eating an extra 3000 calories a day and, honestly, I don’t feel that I even want to.
And, of course, that raises another issue. That typical weight loss graph – sharp decrease in weight, then increase in weight, leveling off a little below the starting weight – that I’ve seen in so many articles is one for the study participants as a whole. But, within the study there is individual variation. Some people never lose much weight. Some lose weight, then regain it all plus more weight (I’ve been there unfortunately). And, there are those few, those very few, who lose all the weight they want to lose and never regain any of it. And, there are those who lose weight and don’t regain most of it, but do regain something.
So, why is there is individual variation? What accounts for it? Genetics is probably part of it. I personally don’t believe that it has much to do with type of diet. Well, that is, I don’t think that there is one perfect diet that anyone can eat and that will have vastly superior weight loss for everyone with no weight regain. I do think that for successful weight loss and maintenance each of us has to find a way of eating that we like and can sustain forever. Someone who is a big beef eater might not be able to successfully stay on a vegan diet for the long haul. We all have personal dietary preferences that cause us to like one way of eating more than others. I don’t think that most of us can sustain weight loss if we are miserable with how we are eating. So, I think diet choice is important in terms of finding a way of eating that we can sustain long-term. And, don’t get me wrong, I am not at all saying that every diet is the same from a health standpoint. I don’t believe that. I think that eating for good health is very important but that is a separate issue from the weight loss issue I am talking about here.
In the study on increased appetite, the authors make the following statement:
The few individuals who successfully maintain weight loss over the long term do so by heroic and vigilant efforts to maintain behavior changes in the face of increased appetite along with persistent suppression of energy expenditure in an omnipresent obesogenic environment. Permanently subverting or countering this feedback control system poses a major challenge for the development of effective obesity therapies.
I added bold to the quote, to really emphasize what I think is important. Maintaining weight loss long terms requires eternal vigilance. Many of us, must constantly watch what we eat, what we do, how we move and so on. I know that there is no point at which I can let up. When I let up, I regain.
As I mentioned above, I don’t think that my appetite has increased by 3000 calories a day. But, I do think it has increased. I have kept a record of what I eat for years. Now, I’m sure it isn’t 100% accurate, but I think that it is fairly consistent from year to year in how I’ve kept it. For this year, I am eating roughly 200 calories a day more than I ate during 2014. Now that was the year of my major weight loss, while this year I have been on maintenance. In 2015, I ate a little more than in 2014 but I was still about 175 calories a day less than this year. Why the increase? Yes, part of it is that I am on maintenance. And, I had all the surgery and during recovery was not a good time to be cutting calories. So, some increase in calories eaten is expected. And, that is all true. Yet, throughout this year I have also wanted to lose a few more pounds. I have recognized that one reason that hasn’t happened is that I am hungrier. I find it difficult to sustain eating at the calorie level I ate at during 2014 and even 2015. I am just hungrier this year. And, I think that is an example of increased appetite.
Now, I haven’t regained. Those graphs of loss then regain don’t apply to me…now. They have applied to me in the past.
See this graph I posted last week after weigh in. On the right is my weight loss graph from when I went back to Weight Watchers in August, 2010. I had the loss and then the regain, but then I lost again and I’ve maintained my goal weight for over a year now.
But, I know that it is only through vigilance that I maintain this loss. Lose focus — as I did last month — and it is all too easy to drift up. My October average calories were almost 300 calories a day more than my average calories a day in 2014.
So, what do we do? When I was putting together this post, I came across a talk that Dr. Kevin Hall did where he discussed many issues relating to weight loss, including both the Biggest Loser study and the new study regarding increased appetite. The talk is called “Myths of Dieting and Weight Loss” and is so worth it to listen to in its entirety.
One of the questions he was asked at the end was about the people who do maintain weight loss and how they do it. He mentioned some research where the researchers talked to people who had lost weight and kept it off and asked them what they do. He mentioned 3 things:
Exercise a lot
To be clear, he wasn’t saying that those things were the cause of the weight loss maintenance, but those were activities commonly found in people who have lost weight and kept it off.
There was something else that Dr. Hall said that stuck with me. In talking about how difficult it is to lose weight and keep it off, he differentiated between people losing weight and improving things from a health standpoint versus losing weight to look better. And, he commented that there are certain things that you can do to your lifestyle that will have health benefits if you can persist with them. Maybe you lose weight, and maybe you don’t, but you can have the health benefits in any event. In my own life, I see that I have done this. I don’t eat (or drink) a lot of sugar. That is beneficial to me in my opinion whether I lose weight or not. I was (until surgery) much more active physically than I used to be. That is good for me, regardless of my weight loss.
But, of course, for most who read this blog or who join Weight Watchers or who try to lose weight, we also want to lose weight and we want to keep it off. And, finding out how to do that is important to us. The reality is that the chances of success can seem awfully grim. But, that is talking about the group as a whole. As an individual, and as a non-expert, I would say that what most helps me to keep weight off is to do what I did while losing weight. I can’t stop doing those things just because I got to a goal weight.
There was a time when I thought I could lose weight and then all would be great. It never occurred to me that my appetite would increase or that I would burn fewer calories than people of my new weight who had never been overweight. One of the things that Dr. Hall talked about in talk I linked to above was this weight loss pattern I’ve mentioned — losing weight for a months, then regaining and leveling off (in his talk, he happened to use Weight Watchers as an example of this). He indicated that people in this position often said that they were still eating the same calories that they had been eating when they were losing weight, but they actually were eating more calories. He did not, however, think they were consciously lying. Rather, he suggested that their effort was the same even though they were eating more calories. So, they felt like they were eating the same amount of calories even though they weren’t.
I can sort of see that. That is, if your body is driving you to eat 1000 extra calories a day and you manage to eat only 500 extra calories a day, then you feel just the same as when you started the weight loss plan and cut 500 calories a day from the diet. But, although, you feel the same you are still eating 500 extra calories a day and gain weight although it feels like you are cutting your diet by 500 calories a day.
So how can we defend against this? For me, tracking what I eat really helps. In his talk, Dr. Hall talks about how most people are terrible at knowing how many calories they eat. And, I know that is true. Still, I think that contemporaneously recording what we eat may help. The reason I know I am eating more now than I was in 2014 is because I tracked my calories. It might not be perfect, but it is better information than no information.
And, to keep on doing what I am doing. This is why it is important to choose a weight loss plan that is something that can be continued long term. If my weight loss plan is to never eat pizza again and I love pizza, then this may not be a plan that I can sustain long term. It is important to ask yourself what you are really willing to do for the long haul. And, then to recognize that getting to goal weight doesn’t really change the intensity of the effort needed to maintain the weight loss.