Researchers claiming it's impossible to keep weight off

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  • likitisplit
    likitisplit Posts: 9,420 Member
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    I read this this morning and laughed. Seriously? They don't think it has anything to do with the fact that people stop sticking to a diet and exercise plan after they've been at goal for a while? Come on. What say you, MFPers?

    http://www.cbc.ca/news/health/obesity-research-confirms-long-term-weight-loss-almost-impossible-1.2663585
    There's a disturbing truth that is emerging from the science of obesity. After years of study, it's becoming apparent that it's nearly impossible to permanently lose weight.

    As incredible as it sounds, that's what the evidence is showing. For psychologist Traci Mann, who has spent 20 years running an eating lab at the University of Minnesota, the evidence is clear. "It couldn't be easier to see," she says. "Long-term weight loss happens to only the smallest minority of people."

    We all think we know someone in that rare group. They become the legends — the friend of a friend, the brother-in-law, the neighbour — the ones who really did it.

    But if we check back after five or 10 years, there's a good chance they will have put the weight back on. Only about five per cent of people who try to lose weight ultimately succeed, according to the research. Those people are the outliers, but we cling to their stories as proof that losing weight is possible.

    "Those kinds of stories really keep the myth alive," says University of Alberta professor Tim Caulfield, who researches and writes about health misconceptions. "You have this confirmation bias going on where people point to these very specific examples as if it's proof. But in fact those are really exceptions."

    Our biology taunts us, by making short-term weight loss fairly easy. But the weight creeps back, usually after about a year, and it keeps coming back until the original weight is regained or worse.

    This has been tested in randomized controlled trials where people have been separated into groups and given intense exercise and nutrition counselling.

    Even in those highly controlled experimental settings, the results show only minor sustained weight loss.

    When Traci Mann analyzed all of the randomized control trials on long-term weight loss, she discovered that after two years the average amount lost was only one kilogram, or about two pounds, from the original weight.

    So if most scientists know that we can't eat ourselves thin, that the lost weight will ultimately bounce back, why don't they say so?

    Tim Caulfield says his fellow obesity academics tend to tiptoe around the truth. "You go to these meetings and you talk to researchers, you get a sense there is almost a political correctness around it, that we don't want this message to get out there," he said.

    "You'll be in a room with very knowledgeable individuals, and everyone in the room will know what the data says and still the message doesn't seem to get out."

    In part, that's because it's such a harsh message. "You have to be careful about the stigmatizing nature of that kind of image," Caulfield says. "That's one of the reasons why this myth of weight loss lives on."

    "You'll be in a room with very knowledgeable individuals, and everyone in the room will know what the data says and still the message doesn't seem to get out."

    In part, that's because it's such a harsh message. "You have to be careful about the stigmatizing nature of that kind of image," Caulfield says. "That's one of the reasons why this myth of weight loss lives on."

    Health experts are also afraid people will abandon all efforts to exercise and eat a nutritious diet — behaviour that is important for health and longevity — even if it doesn't result in much weight loss.

    Traci Mann says the emphasis should be on measuring health, not weight. "You should still eat right, you should still exercise, doing healthy stuff is still healthy," she said. "It just doesn't make you thin."

    But eating right to improve health alone isn't a strong motivator. The research shows that most people are willing to exercise and limit caloric intake if it means they will look better. But if they find out their weight probably won't change much, they tend to lose motivation.

    That raises another troubling question. If diets don't result in weight loss, what does? At this point the grim answer seems to be that there is no known cure for obesity, except perhaps surgically shrinking the stomach.

    Research suggests bariatric surgery can induce weight loss in the extremely obese, improving health and quality of life at the same time. But most people will still be obese after the surgery. Plus, there are risky side effects, and many will end up gaining some of that weight back.

    If you listen closely you will notice that obesity specialists are quietly adjusting the message through a subtle change in language.

    These days they're talking about weight maintenance or "weight management" rather than "weight loss."

    It's a shift in emphasis that reflects the emerging reality. Just last week the headlines announced the world is fatter than it has ever been, with 2.1 billion people now overweight or obese, based on an analysis published in the online issue of the British medical journal The Lancet.

    Researchers are divided about why weight gain seems to be irreversible, probably a combination of biological and social forces. "The fundamental reason," Caulfield says, "is that we are very efficient biological machines. We evolved not to lose weight. We evolved to keep on as much weight as we possibly can."

    Lost in all of the noise about dieting and obesity is the difficult concept of prevention, of not putting weight on in the first place.

    The Lancet study warned that more than one in five kids in developed countries are now overweight or obese. Statistics Canada says close to a third of Canadian kids under 17 are overweight or obese. And in a world flooded with food, with enormous economic interest in keeping people eating that food, what is required to turn this ship around is daunting.

    "An appropriate rebalancing of the primal needs of humans with food availability is essential," University of Oxford epidemiologist Klim McPherson wrote in a Lancet commentary following last week's study. But to do that, he suggested, "would entail curtailing many aspects of production and marketing for food industries."

    Perhaps, though, the emerging scientific reality should also be made clear, so we can navigate this obesogenic world armed with the stark truth — that we are held hostage to our biology, which is adapted to gain weight, an old evolutionary advantage that has become a dangerous metabolic liability.

    Fascinating. I'll keep that in mind as I go into my next bulk.
  • dlionsmane
    dlionsmane Posts: 672 Member
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    This is why I don't care if it takes me 2 years or 10 years to reach my goal. This is what I plan on doing for the rest of my life and as long as my trending is going down I am good with that!
  • impromark
    impromark Posts: 119 Member
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    Thanks, this puts it in perspective. Anyone CAN lose weight. But few people see weight loss as the be-all and end-all of things. Few ask "I've done it; now what?", and thus don't have an idea of what happens when the number on the scale has been reached.

    I started asking myself the "now what" question ever since I acheived a "normal" BMI. I ultimately decided to continue logging MFP to try to get a baseline for what a "proper" maintenance intake looks and feels like, and to continue to work out at least as hard as I've been doing till now. I know that simply stopping will mean the beginning of a slow march back upwards into obseity. BUt I've changed my lifestyle to get here and absolutely will not simply change back now that I'm here. Instead, my lifestyle will include fitness and diet to increase my chances that this part of my life will be the fittest it's ever been.

    Mark
  • litsy3
    litsy3 Posts: 783 Member
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    For me the main limitation in the study is wanting to know where they get the people who participate in the trials. It seems to me that many people just decide that they are going to lose weight, quietly get on with it, and don't ever get on the radar of any health professionals at all. When I decided to lose some weight 5 years ago, I was overweight but not obese, I hadn't spoken to a doctor about my weight, and I lost 45lb which I didn't put back on (and am not likely to now). Whereas if you are doing studies mainly with people who are at an eating clinic, the chances are that a higher proportion of the people already have difficulties with food and eating and may be more likely to relapse.

    The other problem is the language used: 'nearly impossible' is not the same thing as 'not many people manage to do it'. And saying that sustainable weight loss 'doesn't happen to' many people as the woman quoted does already implies that it's nothing to do with individual effort at all!

    Otherwise, there's probably a certain amount of truth in it and I can see the value in re-branding it as 'weight management', which focuses on the importance of a healthy lifestyle and maintaining, which I think we can all get behind.
  • tonynguyen75
    tonynguyen75 Posts: 418 Member
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    The sad part are the comments from people, who most likely, are struggling with their weight. They see an article like this and believe it's impossible, they are genetically like this and there's nothing they can do. So they continue on with their lifestyle and do even attempt to make a change.
  • ekmcdan
    ekmcdan Posts: 38
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    It is indeed a lifestyle change, and something that if you stop paying attention to, may get out of hand.

    I think plenty of researchers will say false things due to the industry that is obesity. We have GMO's that make people eat more and never feel full, we have the trillions of fad diets and exercises, ("Achieve this body in 30 days!" or "take these supplements and change nothing about how you eat! the weight will MELT off") and face it, the food industry makes more money when you buy more food. Fitness is a science.... and if you want fitness, you can have it. It just takes work, like you all are saying. Constant work. Most people who struggle don't seem to find the acheivement in that (I never did before now, believe me: I've yo-yo'd like a *****.)
  • SapiensPisces
    SapiensPisces Posts: 992 Member
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    Low adherence in weight loss is a direct result of the diet industry and other fitness/diet gurus making a fortune off of making people believe that leading a life at a healthy weight is impossible due to (insert boogeyman here). The truth that being healthy (note I'm saying "HEALTHY" here not thin necessarily) requires balance in life and comes from a balance of a healthy outlook on activity and a healthy relationship with food is neither glamorous nor easy to come by.
  • jeanstudies
    jeanstudies Posts: 81 Member
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    These are all great points, the main issue for me is, "what will *I* do after I get down to my GW??" I appreciate general statistical research, but there are always outliers -- and I will have to work to be one of those!

    I also had to laugh, because (at least a few second ago), the post immediately below this one was "4 Year Anniversary Maintaining!" So see not every research study's results applies to everyone. Now that I know the trend I will have to fight really hard to not be part of it. Likely I will have to do a LOT of muscle building after my wrist strain heals and I move out of my Zumba-every-night phase....
  • bcattoes
    bcattoes Posts: 17,299 Member
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    ^^^^ THIS ^^^^ and the one above it (both very good posts)

    one of the biggest problems that I have seen is that most of the diet companies (read WW, South Beach, Jenny, et al) state that the goal is to lose the weight... so people go on the diet and lose the weight and then they are left hanging because NONE of the diet companies has any incentive to help these people KEEP the weight off - they make a TON of money from the yo-yo dieters so why would they want people to keep the weight off???

    losing the weight is only HALF the goal - the other half, the one that none of the fad diets or diet companies teach is keeping the weight off and that takes as much if not more discipline as losing the weight in the first place and the 95% that this article refers to are the people who have only set the goal to lose the weight and not to keep it off!

    I think that is a good point, but I don't think it accounts for everyone. I think a lot of people lose weight planning to keep it off forever. But the fact is to lose weight you have to give up things. You simply can't have the same life you had while gaining weight. Whether you choose smaller portions of the same foods you always ate, or giving up food, or giving up free time to workout, or giving up going out drinking with friends, we all give up something. We all have to change.

    How much you enjoyed your life before the change is an important factor. If you were very obese, what factors caused you to become so overweight is an important factor. Depression, stress, etc. don't always magically disappear with weight loss.

    You were losing for a purpose. Revenge - to make that SO that dumped you regret it, a high school reunion, the big 3-0 or 4-0 or 5-0 birthday, etc. Then that comes and goes and you struggle to find that new motivation.

    The thrill of losing can be a high. People noticing. New clothes. Etc. Then you stop losing. All your clothes fit. Where is the high? This can also be an important factor.

    And then there is life. Your mother has a stroke, a child is seriously hurt or ill, you lose your job and can't pay your gym membership, your spouse has an affair, you are in an accident and any of the other countless stresses that life can throw at us. And there is your old friend food, just waiting to provide comfort.

    What someone losing weight plans isn't always the problem. The best laid plans can go awry.
  • grimendale
    grimendale Posts: 2,153 Member
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    I personally enjoy being a statistical anomaly. The article makes some good points, but the inflammatory rhetoric (1 in 20 is hardly "nearly impossible") makes it hard to get past the initial outrage.
  • Lourdesong
    Lourdesong Posts: 1,492 Member
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    I should probably mention I had to take the "nearly" out of my thread title because of the character limit, not because I misread the article.

    That said, I've never been actually overweight so maybe I just don't get it, but I really don't understand how maintaining the habits developed while losing weight (eating as many or fewer calories as you burn...) could possibly result in regaining weight for people, you know? It doesn't just magically reappear, haha.

    Where did the article suggest those the regained maintained their habits developed while losing weight? It says:

    "Researchers are divided about why weight gain seems to be irreversible, probably a combination of biological and social forces."

    This seems to me to suggest that people slowly go back to old habits. Eating out a little more often, having that extra treat a little more often, shortening or skipping the workouts a little more often, etc.

    The whole article makes it seem like the forces to regain weight are out of anyone's control, including the very next line from the one you quoted: ""The fundamental reason," Caulfield says, "is that we are very efficient biological machines. We evolved not to lose weight. We evolved to keep on as much weight as we possibly can."

    Not to mention the "myth of weightloss" is tossed around quote a bit.

    And finally finishes with this nugget of pseudo-science make-believe:


    "Perhaps, though, the emerging scientific reality should also be made clear, so we can navigate this obesogenic world armed with the stark truth — that we are held hostage to our biology, which is adapted to gain weight, an old evolutionary advantage that has become a dangerous metabolic liability."

    Held hostage by our biology... Not our choices, but our biology. That's what we can draw from the facts. This story. Or can we? Doesn't seem to me that this story logically follows from the facts.

    All this story-telling is superfluous to the facts. Facts which no one denies (i.e. most people who lose weight gain it back), and the story-telling is not something anyone should want from a researcher. Are they paid to greenlight as our local shamans, telling us stories they pulled out of you-know-where? Evo-psych is junk pseudo science, it's superfluous story-telling that is not needed to be coupled with the facts, and any science or scientist who resorts to story-time evo-psych BS should be an object of derision out of principle by everybody. The story-telling almost resembles trolling, because the facts alone aren't interesting to get attention.
  • bizgirl26
    bizgirl26 Posts: 1,808 Member
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    As someone who has yo-yo'ed I know what my downfall is. If you go back to your old ways of course you will gain the weight back. I do fine until I stop weighing myself and stop logging. I know that as hard as it is going to be I have to change my lifestyle for the rest of my life. I cannot ever go back to eating like I did before and I must commit to weighing myself as the weight seems to creep back on without me noticing. Diets dont work, changing your lifestyle habits does. This doesnt stop after we reach our goal weight, its a life long committment of hard work and determination
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
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    How ridiculous! It's not about a "diet" it's a lifestyle change. If you change your mindset about how and what you eat and keep active it is not impossible! It's been almost 2 years of weight loss for me- I weigh almost 100lbs less than when I started.

    Just goes to show that researches don't do a real thorough job- they get an answer they expect and stop and don't continue on to see what those that are truly successful are doing. BAH!

    If your ticker is correct, the article had nothing to do with you. It said it was easy to lose weight. The article is about what happens after you lose the weight. About keeping it off long term. You have no idea if you will do that or not.

    And relying too heavily on a phrase like "lifestyle change" can be dangerous, because it's a pretty good bet that you will go through other lifestyle changes in your life. Many things change our lifestyle - the birth of a child, a child leaving the nest, marriage, divorce, disease, aging parents, death of a loved one, etc.

    I've been through many of these lifestyle changes and will soon face others. I like the word "diet" because my goal is not to keep the same lifestyle, it's to keep the same diet through the lifestyle changes.

    I like this. I lost a bunch of weight one other time in my life--went from 180 to 120--and I truly thought of it as a lifestyle change. I was eating in a way I liked and considered sustainable for life, I didn't count calories when I did it, I thought I'd figured out the reasons I'd been overeating, and I had fun active hobbies that helped a lot, basically running, biking, and swimming, doing lots of outdoor stuff, etc. Kept the weight off for about 5 years and considered myself a success story. I also stopped weighing (always hated weighing myself) but was confident that I'd be vigilant if my clothes got too tight (but then again when I was 20 I would have said that I couldn't see how people became obese, since growing out of your clothes would be such an effective early warning sign--I was obviously wrong). But despite all this, stuff happened and I gradually (or in some ways--like exercise--not so gradually) changed my lifestyle again, and unfortunately my eating with it.

    This is absolutely something I'm thinking about when losing this time. I don't think it's impossible or nearly so--that would be demotivating, I suppose--but it's kind of scary how easily it ended up happening despite everything. One thing is that I will NOT stop weighing myself this time, and I do think counting might be important for me longterm, even if more casually than now.
  • VeganCappy
    VeganCappy Posts: 122
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    This video of Doug Lisle gives an idea of the psychological and physiological aspects of trying to lose weight. Just because some fad diet "feels" right doesn't mean it is good for you.

    https://www.youtube.com/watch?v=jX2btaDOBK8
  • AmyBettenh
    AmyBettenh Posts: 4 Member
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    This article isn't concerning to me because of the facts it highlights (people regain weight they've lost) but because it pushes an agenda. The claim (people can't lose weight and keep it off) and the conclusion (we're the experts; you are the stupid primal people who are engaged in the weight loss myth cycle) point directly to what the desired outcome of the research is: to limit food choices and marketing through regulation because the experts know best. And if anyone for one second believes that this desire comes out of compassion or concern for the health and well being of individuals who are overweight, I've developed a calorie free, weight reducing twinkie you can buy for the right price.

    Success in anything increases when people become accountable for their choices. And what I've found is the more that accountability is to myself and not someone/something else, the more honest I am and the harder I push myself. And if I fail, the failure is on me. Not my biology, not McDonalds, not the food marketers. And I can dust myself off and try again as many times as it takes, learning new things about myself and life in the process. Often those failures are an important ingredient in eventual success. I don't need anyone to step in, pat me on the head, and rescue me from myself because then I stop learning and progressing. This is just my opinion though and why the article bugs me.
  • heatherloveslifting
    heatherloveslifting Posts: 1,428 Member
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    I lost about 45 lbs in 1994 and kept it off until my first pregnancy almost 10 years later. It can be done and I am doing it again. I've spent most of my life doing things other people said were "too hard". I am the 5%.
  • pinkyslippers
    pinkyslippers Posts: 188 Member
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    LOL
    "An appropriate rebalancing of the primal needs of humans with food availability is essential," University of Oxford epidemiologist Klim McPherson wrote in a Lancet commentary following last week's study. But to do that, he suggested, "would entail curtailing many aspects of production and marketing for food industries."

    Hysterical. They're stating that an economy of abundance (here, anyway) and technological convenience has produced people who are eating more than they need. So their solution is apparently to ration out the food, or something similar? In any event, they want to make the food less available. Alternatively, we could just eat less.

    Yes, that's exactly what they are saying in the article in the Lancet - that we all need to eat less, and doing so (in order to get the collective BMI back down to the level it was in 1980) will cost the food industry several billion dollars in lost revenue, which they aren't going to like. I agree with everyone saying it is about individual responsibility, however we live in an environment based on a cheap food model. It would also be interesting to revisit this thread in 10 years to follow up on everyone (myself included) who pledged not to regain the weight. It's complex and bigger than us, at the same time as being down to just us as individuals.
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
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    ^^^^ THIS ^^^^ and the one above it (both very good posts)

    one of the biggest problems that I have seen is that most of the diet companies (read WW, South Beach, Jenny, et al) state that the goal is to lose the weight... so people go on the diet and lose the weight and then they are left hanging because NONE of the diet companies has any incentive to help these people KEEP the weight off - they make a TON of money from the yo-yo dieters so why would they want people to keep the weight off???

    losing the weight is only HALF the goal - the other half, the one that none of the fad diets or diet companies teach is keeping the weight off and that takes as much if not more discipline as losing the weight in the first place and the 95% that this article refers to are the people who have only set the goal to lose the weight and not to keep it off!

    Well, WW does have a maintenance plan and they do supply a very real incentive for people to maintain-- they get the program materials free (online tracking apps, etc.) as long as they're maintaining.

    Though as a whole I think you're right that the solutions address the problems that people want to throw money at: "I'm overweight and I want it off." How many books and plans are being written and sold that address this problem: "My weight is ok and I'd like to keep it that way." Prevention isn't the $$$ industry.
  • in_the_stars
    in_the_stars Posts: 1,395 Member
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    June 10, 2013 11:48 AM
    Ohhhhh...


    Cliffs:
    When your body cannot store any more fat in it's existing cells, it creates new fat cells.
    You cannot get rid of fat cells once your body has created them.
    Thin people don't have as many fat cells in your body, therefore it is harder for thin people to gain weight.


    You might find this interesting. :

    just copying an old post reply.

    While I'm not keen on the entire set - point theory, I do think genetic inheritance plays a very important part in the body returning to a "comfortable" weight. I really think weight is due to a combination of both genes and environment. After reading articles like the following I can't help but wonder if dieting is just too hard for some. My thinking (at the moment ) leans towards the possibility that people who relapse are just tired of the struggle to maintain the constant vigilance. Maybe it's due to a shifting of values where remaining thin is no longer a top priority in life, or counting calories and thinking about food becomes too time consuming and starts taking away from someone's life instead of adding to it. It's nice to be free from analyzing your options every time you eat something, to be able to eat something because that's what you "want", and not what you "should" have.


    I'm sure there are many reasons, just throwing some possibilities out there.


    QUOTE:
    May 8, 2007
    Genes Take Charge, and Diets Fall by the Wayside
    By GINA KOLATA

    It was 1959. Jules Hirsch, a research physician at Rockefeller University, had gotten curious about weight loss in the obese. He was about to start a simple experiment that would change forever the way scientists think about fat.

    Obese people, he knew, had huge fat cells, stuffed with glistening yellow fat. What happened to those cells when people lost weight, he wondered. Did they shrink or did they go away? He decided to find out.

    It seemed straightforward. Dr. Hirsch found eight people who had been fat since childhood or adolescence and who agreed to live at the Rockefeller University Hospital for eight months while scientists would control their diets, make them lose weight and then examine their fat cells.

    The study was rigorous and demanding. It began with an agonizing four weeks of a maintenance diet that assessed the subjects’ metabolism and caloric needs. Then the diet began. The only food permitted was a liquid formula providing 600 calories a day, a regimen that guaranteed they would lose weight. Finally, the subjects spent another four weeks on a diet that maintained them at their new weights, 100 pounds lower than their initial weights, on average.

    Dr. Hirsch answered his original question — the subjects’ fat cells had shrunk and were now normal in size. And everyone, including Dr. Hirsch, assumed that the subjects would leave the hospital permanently thinner.

    That did not happen. Instead, Dr. Hirsch says, “they all regained.” He was horrified. The study subjects certainly wanted to be thin, so what went wrong? Maybe, he thought, they had some deep-seated psychological need to be fat.

    So Dr. Hirsch and his colleagues, including Dr. Rudolph L. Leibel, who is now at Columbia University, repeated the experiment and repeated it again. Every time the result was the same. The weight, so painstakingly lost, came right back. But since this was a research study, the investigators were also measuring metabolic changes, psychiatric conditions, body temperature and pulse. And that led them to a surprising conclusion: fat people who lost large amounts of weight might look like someone who was never fat, but they were very different. In fact, by every metabolic measurement, they seemed like people who were starving.

    Before the diet began, the fat subjects’ metabolism was normal — the number of calories burned per square meter of body surface was no different from that of people who had never been fat. But when they lost weight, they were burning as much as 24 percent fewer calories per square meter of their surface area than the calories consumed by those who were naturally thin.

    The Rockefeller subjects also had a psychiatric syndrome, called semi-starvation neurosis, which had been noticed before in people of normal weight who had been starved. They dreamed of food, they fantasized about food or about breaking their diet. They were anxious and depressed; some had thoughts of suicide. They secreted food in their rooms. And they binged.

    The Rockefeller researchers explained their observations in one of their papers: “It is entirely possible that weight reduction, instead of resulting in a normal state for obese patients, results in an abnormal state resembling that of starved nonobese individuals.”

    Eventually, more than 50 people lived at the hospital and lost weight, and every one had physical and psychological signs of starvation. There were a very few who did not get fat again, but they made staying thin their life’s work, becoming Weight Watchers lecturers, for example, and, always, counting calories and maintaining themselves in a permanent state of starvation.

    “Did those who stayed thin simply have more willpower?” Dr. Hirsch asked. “In a funny way, they did.”

    One way to interpret Dr. Hirsch and Dr. Leibel’s studies would be to propose that once a person got fat, the body would adjust, making it hopeless to lose weight and keep it off. The issue was important, because if getting fat was the problem, there might be a solution to the obesity epidemic: convince people that any weight gain was a step toward an irreversible condition that they most definitely did not want to have.

    But another group of studies showed that that hypothesis, too, was wrong.

    It began with studies that were the inspiration of Dr. Ethan Sims at the University of Vermont, who asked what would happen if thin people who had never had a weight problem deliberately got fat.

    His subjects were prisoners at a nearby state prison who volunteered to gain weight. With great difficulty, they succeeded, increasing their weight by 20 percent to 25 percent. But it took them four to six months, eating as much as they could every day. Some consumed 10,000 calories a day, an amount so incredible that it would be hard to believe, were it not for the fact that there were attendants present at each meal who dutifully recorded everything the men ate.

    Once the men were fat, their metabolisms increased by 50 percent. They needed more than 2,700 calories per square meter of their body surface to stay fat but needed just 1,800 calories per square meter to maintain their normal weight.

    When the study ended, the prisoners had no trouble losing weight. Within months, they were back to normal and effortlessly stayed there.

    The implications were clear. There is a reason that fat people cannot stay thin after they diet and that thin people cannot stay fat when they force themselves to gain weight. The body’s metabolism speeds up or slows down to keep weight within a narrow range. Gain weight and the metabolism can as much as double; lose weight and it can slow to half its original speed.

    That, of course, was contrary to what every scientist had thought, and Dr. Sims knew it, as did Dr. Hirsch.

    The message never really got out to the nation’s dieters, but a few research scientists were intrigued and asked the next question about body weight: Is body weight inherited, or is obesity more of an inadvertent, almost unconscious response to a society where food is cheap, abundant and tempting? An extra 100 calories a day will pile on 10 pounds in a year, public health messages often say. In five years, that is 50 pounds.

    The assumption was that environment determined weight, but Dr. Albert Stunkard of the University of Pennsylvania wondered if that was true and, if so, to what extent. It was the early 1980s, long before obesity became what one social scientist called a moral panic, but a time when those questions of nature versus nurture were very much on Dr. Stunkard’s mind.

    He found the perfect tool for investigating the nature-nurture question — a Danish registry of adoptees developed to understand whether schizophrenia was inherited. It included meticulous medical records of every Danish adoption between 1927 and 1947, including the names of the adoptees’ biological parents, and the heights and weights of the adoptees, their biological parents and their adoptive parents.

    Dr. Stunkard ended up with 540 adults whose average age was 40. They had been adopted when they were very young — 55 percent had been adopted in the first month of life and 90 percent were adopted in the first year of life. His conclusions, published in The New England Journal of Medicine in 1986, were unequivocal. The adoptees were as fat as their biological parents, and how fat they were had no relation to how fat their adoptive parents were.

    The scientists summarized it in their paper: “The two major findings of this study were that there was a clear relation between the body-mass index of biologic parents and the weight class of adoptees, suggesting that genetic influences are important determinants of body fatness; and that there was no relation between the body-mass index of adoptive parents and the weight class of adoptees, suggesting that childhood family environment alone has little or no effect.”

    In other words, being fat was an inherited condition.

    Dr. Stunkard also pointed out the implications: “Current efforts to prevent obesity are directed toward all children (and their parents) almost indiscriminately. Yet if family environment alone has no role in obesity, efforts now directed toward persons with little genetic risk of the disorder could be refocused on the smaller number who are more vulnerable. Such persons can already be identified with some assurance: 80 percent of the offspring of two obese parents become obese, as compared with no more than 14 percent of the offspring of two parents of normal weight.”

    A few years later, in 1990, Dr. Stunkard published another study in The New England Journal of Medicine, using another classic method of geneticists: investigating twins. This time, he used the Swedish Twin Registry, studying its 93 pairs of identical twins who were reared apart, 154 pairs of identical twins who were reared together, 218 pairs of fraternal twins who were reared apart, and 208 pairs of fraternal twins who were reared together.

    The identical twins had nearly identical body mass indexes, whether they had been reared apart or together. There was more variation in the body mass indexes of the fraternal twins, who, like any siblings, share some, but not all, genes.

    The researchers concluded that 70 percent of the variation in peoples’ weights may be accounted for by inheritance, a figure that means that weight is more strongly inherited than nearly any other condition, including mental illness, breast cancer or heart disease.

    The results did not mean that people are completely helpless to control their weight, Dr. Stunkard said. But, he said, it did mean that those who tend to be fat will have to constantly battle their genetic inheritance if they want to reach and maintain a significantly lower weight.

    The findings also provided evidence for a phenomenon that scientists like Dr. Hirsch and Dr. Leibel were certain was true — each person has a comfortable weight range to which the body gravitates. The range might span 10 or 20 pounds: someone might be able to weigh 120 to 140 pounds without too much effort. Going much above or much below the natural weight range is difficult, however; the body resists by increasing or decreasing the appetite and changing the metabolism to push the weight back to the range it seeks.

    The message is so at odds with the popular conception of weight loss — the mantra that all a person has to do is eat less and exercise more — that Dr. Jeffrey Friedman, an obesity researcher at the Rockefeller University, tried to come up with an analogy that would convey what science has found about the powerful biological controls over body weight.

    He published it in the journal Science in 2003 and still cites it:

    “Those who doubt the power of basic drives, however, might note that although one can hold one’s breath, this conscious act is soon overcome by the compulsion to breathe,” Dr. Friedman wrote. “The feeling of hunger is intense and, if not as potent as the drive to breathe, is probably no less powerful than the drive to drink when one is thirsty. This is the feeling the obese must resist after they have lost a significant amount of weight.”

    This is an excerpt from Gina Kolata’s new book, “Rethinking Thin: The New Science of Weight Loss — and the Myths and Realities of Dieting” (Farrar, Straus & Giroux).

    Correction: May 12, 2007
    An article in Science Times on Tuesday about the role of genes in weight gain misstated the publication date for an article in the journal Science describing the biological controls over body weight. The article was published in 2003, not 2000.


    *Lots of comments after this article at the New York Times if you're interested - most not as depressing as this article and a few by readers that are maintaining a large loss of weight.





    *To be honest though, I think in certain cases obesity might be related to viruses, microbes, bacterium, and such. adenovirus -36? Methyl markers aren't the only way genes are turned on or off. Promoters and repressors that regulate how much a gene expresses itself into mRNA? and then translating into a protein?