Research Review: The Biggest Loser study Is it impossible to sustain weight loss in the long term?The Biggest Loser - canceled TV shows. Contestants lost hundreds of pounds during Season 8, but gained them back. A study of. ![]() ![]() ![]() ![]() ![]() Research Review: The Biggest Loser study. Is it impossible to sustain weight loss in the long term? What happens to the body weights and metabolisms of The Biggest Loser contestants after they appear on the show? And what does this mean for everyone else who wants to lose weight and keep it off?++++Nine in 1. So it’s no wonder the NBC reality show The Biggest Loser has become wildly popular. Competitors running on treadmills with tears streaming down their faces. Trainers screaming motivational slogans? A just- released study — shedding not- so flattering light on what happens after the show — suggests not. Here’s the media narrative of what happened: The Biggest Loser contestants regain most (or all) of the weight once cameras get turned off. This is caused by and/or leads to damaged metabolisms, psychological trauma, and shame. Trying to lose weight and keep it off is hopeless. But is this story true? What does the study prove? And is it really impossible to sustain weight loss? Let’s dig a little deeper. Research questions: What happens to the body weights and metabolisms of The Biggest Loser contestants in the years after they appear on the show? What does this mean for regular folks who want to lose weight and keep it off? Fothergill E, Guo J, Howard L, Kerns JC, Knuth ND, Brychta R, Chen KY, Skarulis MC, Walter M, Walter PJ, Hall KD. Persistent metabolic adaptation 6 years after “The Biggest Loser” competition. Obesity (Silver Spring). For good health and physical function, we want less fat mass and more lean mass in general. Resting metabolic rate (RMR) is the number of calories a resting body burns in a day, without activity. Weight loss aside, smaller bodies require less energy to maintain and should have lower RMRs. Bigger bodies require more energy and should have higher RMRs. Leptin levels: Leptin is a hormone that, among other things, gets released after we eat, suppressing our appetite and increasing energy expenditure to help keep our calories in/calories out balanced and our weight stable. In general, the more fat cells in your body, the higher your leptin. Since leptin helps regulate RMR, the two should rise and fall together. Now, in case you’re not caught up on your reality TV watching, here are a few important things to know. When the filming starts, The Biggest Loser participants are morbidly obese (exceeding their ideal weight by 1. Over the course of 3. Contestants eat a diet restricted to about 1. Contestants do at least of 9. After filming the show, contestants return to “real life” without continued supervision or guidance as to how to maintain their nutrition and exercise regimen.
The Biggest Loser: Couples 2 is the seventh season of the NBC reality television series The Biggest Loser. The season premiered on January 6, 2009, with eleven. Watch full episodes of The Biggest Loser and get the latest breaking news, exclusive videos and pictures, episode recaps and much more at TVGuide.com. Methods. Initial assessment. Before their first appearance on the show in 2. RMR (in other words, basic metabolic activity of being alive)physical activity expenditure (in other words, exercise)total energy expenditure (how much energy people were expending in a day through metabolism and physical activity together); andblood chemistry. Follow up. In 2. 01. Two weeks before the study officially started, participants weighed themselves on a special digital scale that transmitted their data to the researchers. This early start helped ensure that people didn’t try to change their weight before the study began, which would skew the results. Once in the lab, researchers again measured the subjects’ RMR, total energy expenditure, and physical activity expenditure. They also performed bloodwork. They then compared the results of their 2. Here are the results. This is about 5. 00 fewer calories than we’d expect them to burn based on predictive equations that take into account their body weight. Lean body mass (an indication of muscle mass)Average lean body mass before filming: 1. Average lean body mass after 3. Average lean body mass six years after final weigh- in: 1. Participants lost 2. They did end up gaining about 1. However, that didn’t help to elevate their RMR, as we might have expected. Leptin. Average leptin before filming: 4. LAverage leptin after 3. LAverage leptin six years after final weigh in: 2. LAs you’d expect, participants’ leptin levels went down when fat decreased, and went up again when fat came back. So, why did they regain the weight? That’s a complicated question. But the study’s findings give us big clues, and new discoveries for our understanding of metabolism. Many people assume that weight loss — and sustaining weight loss — is purely psychological. If you don’t have the mental strength and willpower to pass on the chili cheese fries, then you’re essentially choosing to gain back the weight, right? But the Biggest Loser data illuminate the important physiological roadblocks contestants face. Metabolic adaptation. We already know that when you lose weight, your metabolism slows. This is called metabolic adaptation, and it’s normal. Metabolic adaptation is a natural defense mechanism against starvation. When you’re dieting, at a certain point, your body will send up a red flag. Starvation alert! There’s not enough food to go around! Hold onto the fat reserves! At that point, your RMR slows. Metabolic adaptation can make things more complicated (and frustrating) for dieters who hope to continue or maintain their weight loss. Once their body’s red flag goes up, calorie restriction no longer has the same effect it did at the beginning of their diet. Suddenly, they need to cut more calories just to maintain the same weight. While this is sometimes framed as metabolic damage, it’s really just your body’s way of trying to keep you alive and well. What was interesting about this study? It showed that participants’ RMR stayed low despite: Weight regain: Even though participants were larger six years later, they weren’t burning more calories at rest. Muscle maintenance: Theoretically, the more muscle you have, the more calories you burn at rest. But it’s not helping these participants’ RMR. Time passing: We used to think that metabolic adaptation may reverse with time, and it might. But here we see that even six years isn’t enough. In the end, as you can see in the following graph, participants’ metabolisms were just as low after six years (and after regaining almost 1. When they regained weight, leptin rose accordingly. But there are two sticking points here: “Normal” leptin doesn’t mean it’s easy to control your appetite. Pre- Biggest Loser, these folks were used to eating a certain amount; now they need less to stay smaller. Of course, if they (unconsciously) went back to those same amounts, rather than following their natural physical satiety signals, it’s easy to understand why they gained weight. The participants’ leptin and RMR are no longer linked. If the two usually rise and fall together, why didn’t RMR go back up — as leptin did — when the weight was regained? This could also lead to weight regain. Even if participants followed hunger cues and stopped eating when satisfied, they’d be eating more than needed considering their low RMR. Putting all this together, in order to sustain their weight loss, The Biggest Loser participants would have to: Eat 5. That’s 2. 5 percent less than a person who always weighed 1. Or. That’s an intense workout — like running fast for an hour. All while. Again, the participants’ leptin levels may be normal — but since their metabolic rate didn’t rise with it, eating with their physical hunger cues may actually cause them to consume more calories than they’re burning. Yea, that sucks. No wonder these folks have trouble keeping the weight off. Does this mean it’s impossible to sustain weight loss? It’s clear that, when you lose a lot of weight, you’re up against a lot of very real physiological changes if you want to maintain the weight loss. But there’s a lot of important information we don’t have about The Biggest Loser contestants. What goes on behind the scenes? The Biggest Loser is a television program. It’s not itself a controlled research group or scientific experiment. With this study, researchers are trying to make sense of what happened after the fact. The initial conditions themselves are mostly a mystery. That means all kinds of factors could have influenced the outcomes. What kinds of foods were they eating? Were they eating whole foods or processed “diet” foods? Did they take any supplements or drugs? Could psychological stress have played a role? We just don’t know. But all of these factors could affect the contestants’ ability to sustain weight loss. What are the participants’ lives like? The participants reported maintaining the Biggest Loser- approved nutrition regimen and exercise level over the six- year period. But: Self- reported data are notoriously unreliable. It’s not a flaw of these particular people, it’s just how humans work. Some of the participants were able to keep weight off for years before it returned. So questions arise like: Is the weight regain the result of unfortunate physiology, exclusively? Are they eating more and exercising less than they think they are? Is psychological stress from weight regain in a public setting playing a role? Here again, we don’t have answers, and all of this can affect a person’s ability to maintain their weight. Did they regain the weight because they lost it so quickly? The Biggest Loser program helps contestants lose weight at a rate you rarely see elsewhere. Many people are speculating that this is the reason for the participants’ persistent metabolic adaptation and weight regain. That’s a convenient explanation, but not necessarily an accurate one. Another study compared The Biggest Loser participants’ weight loss with gastric bypass (Roux- en- Y) patients about six months after surgery and found something surprising. The two groups lost a comparable amount of weight in half a year, but the gastric bypass patients experienced half the metabolic adaptation. After a full 1. 2 months, and after losing even more weight, the gastric bypass group had a very slightly higher metabolism than predicted (+8 calories per day). The Biggest Loser (a Titles & Air Dates Guide). The home sites for this guide are.
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