11 ms·

A Mathematical Challenge to Obesity

101 points by ckuehne 14y ago

Almaviva 14y ago
"An extra 10 calories a day puts more weight onto an obese person than on a thinner one." It needs to be explained how he determined that this isn't related to _why_ they are obese in the first place, i.e. whether these are purely correlational facts. It would be nice if the New York Times wasn't susceptible to elementary statistical fallacies like this but... well this is nutrition after all.
- streptomycin 14y ago
  An interview in the New York Times is not an academic research paper. In this context, it's reasonable for the interviewer to take the mathematician's word for it rather than hammering away at a pedantic detail that may or may not be relevant.
  - Almaviva 14y ago
    This would be reasonable if people who ought to know better didn't commit this kind of elementary error constantly, particularly in nutrition. It is your attitude, that it's reasonable to publish a scientific article in a major publication without independent thought and fact checking, that I am challenging.
    - scott_s 14y ago
      it's reasonable to publish a scientific article in a major publication without independent thought and fact checking The person you are replying to did not say or imply that.
- howeyc 14y ago
  There was a documentary on HBO recently that stated this as well. What's going on is that someone who is obese needs less calories per day to maintain their weight than someone who is not obese. Something to do with metabolism rates slowing down when you are overweight. See "Weight of the nation."
  - colomon 14y ago
    Except that's completely backwards to any "calories needed" calculation I've ever heard before. For instance, I just tried http://caloriecount.about.com/cc/calories-goal.php http://caloriecount.about.com/cc/calories-goal.php (after googling it out of the blue) with starting weights of 300 and 200, ten pounds to lose both ways, everything else the same. The calculator suggested the 200 pound guy needed to eat 500 calories a day fewer than the 300 pound guy did.
    - waterlesscloud 14y ago
      It's just a calculator on the internet, based on some simple formula. If experimental data says otherwise, the calculator is simply wrong.
      - drostie 14y ago
        While this is true, it is not particularly enlightening. The problem is that earlier a definite assertion was made that obese people burn fewer calories per day when staying at the same weight, and colomon was saying that this is known to be contradicted by certain experimental facts. It is known from experiment that basal metabolic rates are larger as your weight goes up. It's even consistent with a simple causal model. Obese people have larger bodies, which require more maintenance -- a larger supply of blood vessels and a heart working harder to fill them, more energy expended in getting up and going to the bathroom, et cetera. So it's kind of "no mystery." Now, it might still be the case that this documentary was correct -- for example, while basal rates might be higher for obese people, perhaps normal-weight people simply have an exercise routine which increases their metabolism in general. Something like that would be useful and would help colomon understand why the result is backwards. Unfortunately, I didn't see the documentary and therefore I don't know this particular reason, but the question is legitimate and is not well-dismissed simply by saying, "oh you know that crazy internet."
      - whatusername 14y ago
        So the Hans Benedict formula (which has been in use since 1919) is directly weight related. The Katch-McArdle and Cunningham try to be more specific and relate to the Lean Body Mass (LBM). However -- since LBM is reasonably correlated with overall weight -- then we can assume that (all else being equal) the fatter person has a higher BMR.
- Wilduck 14y ago
  Thanks for bringing this up, I'd really like some statistical awareness to show up in science reporting. > It needs to be explained how he determined that this isn't related to _why_ they are obese in the first place, i.e. whether these are purely correlational facts. I would settle for a simple statement that "An extra 10 calories a day puts more weight onto an obese person than on a thinner one," all else equal or controlling for other factors. So much of science is based off accepting statistical evidence, that it would be invaluable for science reporting to state, at least in laymans terms, the statistical veracity of results. In this case such a statement should be even easier since we're dealing with a theoretical model of obesity. Is there a coefficient for "current weight" that is independent of other factors?
- byoung2 14y ago
  It needs to be explained how he determined that this isn't related to _why_ they are obese in the first place I agree that more explanation is needed...the thinner person may be thin because she is more active, and the obese person may be obese because she is more sedentary. An extra 10 calories would seem more likely to put more weight on a sedentary person than an active one.
  - glenra 14y ago
    The reverse claim has just as much explanatory power. That is to say: The active person may be active because she is more thin, and the sedentary person may be sedentary because she is more obese.
- dbecker 14y ago
  I've only flipped through this so far, which obviously isn't enough to fully grasp the argument. But you can find the researcher's reasoning explained in his slides at : http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf
opiumden 14y ago
It's nice to see that people are developing new models and ways of thinking about weight loss but I wonder how effective this research is going to be. The conclusion of the article is the same old "eat less and eat healthier" which is fantastic advice ... and advice that a great many people don't bother to follow. As a culture we're eating ourselves to death while worrying that low probability events like terrorist attacks are going to kill us. We're killing us and we're doing it slowly.
- Retric 14y ago
  Well, stop subsidizing farmers is probably a good takeaway.
  - jrockway 14y ago
    I doubt anyone is getting fat from raw whole foods.
    - Drbble 14y ago
      Farm subsidies are largely for corn products and for non-production of overproduced commodities.
- potatolicious 14y ago
  > "which is fantastic advice ... and advice that a great many people don't bother to follow" At least a large part of this is due to lack of education. For all the time we spend on math and science in public schools, we spend none of it on some basic principles like nutrition. I was rather obese in high school, and the (Canadian) government foot the bill for nutrition courses and consultations with a dietitian (this is a big can 'o worms too: preventative programs like this are way easier in a single-payer system). I now have the ability to judge what's good for me, and what isn't, as well as effective alternatives to existing choices. That knowledge has been instrumental in my weight loss. The problem with that "fantastic advice" is that it's rarely coupled with real constructive suggestions. "Eat less and eat healthier, fatass" is unproductive when the person lacks the knowledge to make effective choices, and alternatives to break entrenched habits aren't presented. Sure, a Big Mac is universally unhealthy, but what do you replace it with? A grilled cheese sandwich isn't much better, nor are a lot of "healthier looking" alternatives (anything with mayo slathered in it is dietary suicide, regardless of how much greens you stick in it also). How do you curb hunger when in the process of downsizing your portions? Curling up in a corner isn't super effective. Blood sugar management throughout the day to get you through the rough patches? None of this is trivial knowledge. Of course, the factor making all of this substantially worse is that the signal to noise ratio in dietary literature is horrific. For every real, researched book on effective diets, you have 3 more fad diets backed up by voodoo and pseudoscience.
brd 14y ago
The Omnivore's Dilemma (Michael Pollan) goes into more detail on the history of the food boom in the 1970s and its link to obesity. Its a great read for anyone interested. Essentially we got hit with a one-two punch of food price paranoia and the high fructose corn syrup innovation.
- saddino 14y ago
  I'd also recommend The End of Overeating (David Kessler) which posits that the obesity explosion is due to recent advances in food science re: foods engineered (precise ratios of fat, sugar and salt) to make you want to eat more ("conditioned hypereating"). If you want to lose weight, stop eating packaged food, cut out fast-food and cut back on restaurants/take-out. Make your own food (like everyone did 40 years ago for most meals) and you'll find yourself controlling your portion intake by default.
  - wpietri 14y ago
    I second that. In April I tried an experiment: home-cooked meals at least twice a day, and nothing with a human-boosted glycemic load. E.g., nothing with added sugar, no refined carbs, no fruit juice. Portion control was much, much easier. I still ate until I felt full; I just felt full a lot sooner, and experienced a big drop in between-meal cravings.
  - deleted 14y ago
    [deleted]
csmeder 14y ago
"What caused the obesity epidemic?" "And it’s something very simple, very obvious, something that few want to hear: The epidemic was caused by the overproduction of food in the United States. ...This, of course, is a tremendously controversial idea. However, the model shows that increase in food more than explains the increase in weight." This is analogous to saying: "What caused the increase in car accidents?" "And it’s something very simple, very obvious, something that few want to hear: The car accident epidemic was caused by the overproduction of cars in the United States. ...This, of course, is a tremendously controversial idea. However, the model shows that increase in cars more than explains the increase in car accidents." By using the phrase "overproduction of food" he is using too broad of a statement that doesn't describe the problem in an addressable way. It makes it sound like we could just cut food production across the board and prevent obesity. . I would argue the problem isn't the quantity, rather the quality. Quality in regards to: - Nutrients vs Fat and sugars - Number of meals a day and the time we eat those meals - Sugary drinks vs Water - Appropriate meal size - Fast food vs home made meals The solution for the 21st century is going to take more than cutting food production. Just as curbing injuries from car accidents will take a different approach than limiting US car production.
- alexandros 14y ago
  > I would argue the problem isn't the quantity, rather the quality But you didn't, argue. You simply asserted. You threw out the article's theory by constructing a straw-man you didn't even bother tearing down, then proceeded to inform us of your views.
  - aMoniker 14y ago
    Actually, he said that he 'would' argue. So he is not actually arguing, but informing us that if necessary, an argument could be constructed based on the view he presented.
  - brady747 14y ago
    You are right, but he didn't say he was arguing in his comment, he said he would. :)
mhartl 14y ago
You are an M.I.T.-trained mathematician and physicist. How did you come to work on obesity? ...I didn’t even know what a calorie was. I call bullshit.
- theorique 14y ago
  Exaggeration for effect? It's perfectly plausible that a mathematician / physicist would have a weak layman's understanding of energy balance in nutrition.
  - mhartl 14y ago
    You're probably right. Maybe in an audio interview the irony would have come through.
- eugenejen 14y ago
  Why do you say it as bullshit? One important thing in higher education for math and physics is to be able to perform detail technical computations or modeling for phenomenons. In common high school and undergraduate physics class, it only requires students to be able to come up models with intuitions. But in graduate schools, you are trained to examine each step to make sure nothing is left out or based on assumptions that are wrong in your mind. Therefore a lot of time you are not sure what something is until you re-examine all postulates that you learn when you are young.
  - kalid 14y ago
    > Why do you say it as bullshit? An MIT-trained physicist should know the common name for a unit of energy. Sure, he might not remember the conversion from joules to calories, but to have never heard of it? That's taking a literal reading ("I didn't know what a calorie was"), but perhaps he was referring to a more nuanced understanding ("I didn't understand how energy was used by the body"). That interpretation wasn't clear from the text though -- it seemed an overwrought attempt to portray an "Aw shucks, I didn't know what I was doing!" attitude.
vsviridov 14y ago
tl;dr - eat less
lukifer 14y ago
Math alone is the wrong tool to solve a problem that is biochemical and behavioral in nature. On an individual level, the fix is straight-forward: eat more "good" fats, and little or no grains and sugars. I have yet to encounter someone who has done this and not seen dramatic results. It's a trickier problem on a broad sociological level, though. The sugar peddlers have an incentive to create and maintain the addiction, and yet they're also just giving people what they want, and at the end of the day, it's still a free country. We can't ever expect all people to abandon sugar any more than all people have abandoned smoking. As much as I hate to agree with libertarian dogma, I think the USDA is a big part of the problem. They've been been promoting high-carb diets and "moderate" sugar consumption for decades, and it certainly smells like yet another government-industrial complex protecting existing profits.
- ticks 14y ago
  Those high-carb diets were probably useful several decades ago, especially in countries that suffered from the world wars. I think it had good intentions but due to those commercial influences, the advice wasn't adapted to fit modern lifestyles.
- zkirill 14y ago
  >> eat more "good" fats, and little or no grains and sugars. Grains, specifically cereal grains, may serve as a limited dietary source of fiber, essential amino acids, vitamins, and minerals. As with everything, it is best to exercise moderation but I wouldn't recommend fully removing grains from the diet. Refined (table) sugar is a common offender but small dosages of fructose and sucrose from a daily serving of fresh fruits and vegetables are justifiable.
  - sliverstorm 14y ago
    Oats are a grain, and I've never heard anything but praise for oats, from anyone. Such things as russet potatoes are probably more questionable than oats, for example, as I believe they are almost entirely starch.
    - 14y ago
its_so_on 14y ago
I disagree with the article, and don't believe mathematics has the answer to obesity. However, if someone would like to start a diet-centered startup with me, I believe I have an insight that invalidates every diet book on the planet. Every diet book on the planet makes one very false assumption. Before we get to the assumption, let's review something uncontroversial: - You put on fat by eating more calories than you use; and you lose fat by using more calories than you eat. In other words, losing fat (beating obesity) would seem to be a combination of "diet and fitness". If you like, you can view every diet book on the planet as a combination of strategies that fall into those two categories (eat less or use more of the calories). So how can ALL those strategies be wrong? Let's turn the equation "net fat gain = calories in - calories out" into something more familiar. "net bank account gain = money in - money out." is it really so simple? Yes. Everyone who weighs more than they want has more money in their bank account (more Calories on their body, ready to burn off) than they want. Now to get to the big diet books' fallacy, let's turn this around. You're a multimillionaire and want to lose half of your money. What's the easiest way to do it? The easiest way to do it, if you're a millionaire, is to call up your accountant and say, "I would like to donate half of my money to Bill and Melinda Gates foundation, please arrange this." That's a strategy. You can write it down on a piece of paper and fax it to your accountant with your signature on the bottom, after a few more signatures it's done. So, what is the difference between THIS strategy and a DIET strategy? Simple: When you wrote that down to fax your your accountant (or booked a hotel room by email, or booked an appointment with a repairperson, contractor, whatever, basically anything like that) then the strategy you wrote down and faxed, in that fax, had the effect that the person it addresses WILL OBEY YOUR COMMAND. They will follow your strategy. Whereas, if you decide "every morning 5 pushups" and write it down, even if you fax it to yourself that does NOT mean that its recipient (you) will do 5 pushups the next morning. In other words, every diet book on the planet thinks that you are the boss of the person doing the dieting and exercising, and simply have to micromanage what they do. But you are NOT the boss of you. Let's recap. Writing: "Dear ---, After careful deliberation I have decided that I will immediately be donating 1/2 of all of my wealth to the Bill and Melinda Gates foundation. Please liquidate an appropriate portion of my investments in stocks, bonds, and mutual funds (in equal measure) for me to to be able to donate half of my net worth, and then prepare the donation for my signature. Yours truly," now it will start to happen, and another signature or two and it's done. (Even if this was considerable work for the accountant!!!) Now write down: "Starting tomorrow morning, as soon as you wake up please ensure your first action is to do 5 pushups and 5 situps. For seven days do so, then for the next week do 10 of each, the next week 15 of each, then 20, and os on, until you reach 50 of each (after 10 weeks), which you should keep doing indefinitely. Yours truly, yours truly." Simple strategy, right? Only problem is, if you fax it to yourself, I can almost guarantee you that the recipient of the fax will not do what you want. Even if you sign it. Even if you really, really want you recipient to follow through. They won't. Every single diet book makes the SINGULAR mistake of thinking that its reader is free to choose a strategy of consumption and of exercise. Not so: the reader can agree with every word. Unlike agreeing with every word of investment advice that a rich person can order an accountant to follow through on, the reader of any diet book has no such power to order that a strategy (of either diet or of exercise) be executed. - read about Tahiti, decide you want to see it, call your travel agent and have them book a room in Tahiti, and a room will be booked in Tahiti. - read a fad diet, decide you want to see the results, and... no guarantee you will have a chance to see them. In sum, if you see what is wrong with the present offering, please email me for collobaring on an interesting alternative.
paul-woolcock 14y ago
The "calories in/calories out" argument is based on the assumption that the human body is a closed system. This is simply not the case, and touting it as a diet strategy is irresponsible. You might lose weight if you lower your caloric intake by only eating 1 McDonalds cheeseburger a day instead of 2, but in the end you are still eating crap food "product", and you won't be as healthy as you could be by focusing on the _quality_ of your food as opposed to the _quantity_.
- robomartin 14y ago
  Well, there's loosing weight and loosing body fat. Two very different things. Two visibly different things.
- getsat 14y ago
  There's a few National Institute of Health studies that back the calories in vs calories out argument. Keep your calorie intake below your BMR (basal metabolic rate) + what you burn during the day if you want to lose weight. Very simple. You don't have to "balance saturated and unsatured fats", get ten hours of sleep per day, or whatever other ridiculous microoptimisations people come up with. Eat 500 calories below your MBR + burn rate and you lose one pound per week. You can do it while eating garbage food (fast food, heavily processed food products) or you could do it while eating a totally vegan diet. It doesn't matter for weight loss.
  - Drbble 14y ago
    Look up "compliance" and how it relates to self-applied medical care for nutrition, acne, exercise, birth control, etc. Vasectomy is more effective than pill is more effective than condom, not because of chemistry or biology or physics, but because of psychology.
  - paul-woolcock 14y ago
    That makes sense. I suppose I just think of something different than I should when I hear "weight loss." When someone says "weight loss," I hear "body composition change," which is obviously different than weight loss.
robomartin 14y ago
"And it’s something very simple, very obvious, something that few want to hear: The epidemic was caused by the overproduction of food in the United States." Overproduction? Does a factory intentionally produce more cars than it can sell? Probably not. How about a baker? Does a baker produce more cookies than she can sell? Not for long. Maybe a farmer? No. Not really. That is not an economically sustainable position to take. If we take the "overproduction" assertion as fact, this begs the question: Why is this happening? One answer is that consumers have more money to spend and they are choosing to spend some of it buying (and consuming) more food. Fair enough. Another answer could be that, in certain segments, government geniuses decided they know better than to let free market work. They go in and throw money around to make producers do what they would not under normal circumstances. That triggers over-production of certain goods. Which triggers lower prices. Which triggers higher consumption. And so on. Another possible answer is a combination of the above. I am, admittedly, against government meddling in our lives. I want them out of nearly everything. Go throw parties for foreign dignitaries and balance our books. Maybe do a few more things. Oh, yes, those borders. Deal with them will ya? Any time these guys dip their ignorant toes into the water of our lives they invariably create a mess that our children and our children's children will have to pay for. Of course, this philosophy extends to self-responsibility. In my family we might have a soft drink or two at parties here and there. Just like having ice-cream, in moderation it is an occasional treat. Aside from that, water only. What the hell is wrong with people that go into a gas station and order a 64 ounce soft drink? That's like consuming a cup full of sugar while you drive to work. This is where another angle in this equation comes into play: A third-payer system of health does not penalize bad behavior. Someone who is a complete moron when it comes to how they take care of their bodies and what they put into it should suffer the financial consequence of having to pay a lot more for healthcare. Today, those of us who try to be sensible are paying for the idiots who are not. That is fundamentally wrong. If you want a healthy and slim population, again, get government the hell out of the way. Yes, it can be that simple. Don't manipulate markets and don't get involved in healthcare. People should buy and pay for their own health insurance, just like they do car insurance. If you drive like a mad-man and get tickets and accidents your insurance goes up or it could be cancelled. The end result is that people modify their behavior to what is a financially sensible state. The same would happen with healthcare if people were directly responsible for their own insurance and suffered the consequences of their dumb decisions. Smoke and destroyed your lungs? Your insurance should cost you $50K per year. Enjoy. Drink alcohol like an animal and turned your liver into mush? $75K a year. Have fun. The rest of us would have sensible policies which would reward us for being responsible while covering us in the case of catastrophic events or serious illness outside of our control. To be clear, I don't have a problem contributing to the pot to help out those afflicted with cancer or similar horrible diseases. A portion of everyone's premiums would cover these out-of-the-norm cases. Then there's the case of obesity caused by diseases like Cushings Syndrome (pituitary gland tumor) that's potentially deadly and has nothing to do with over-eating. We need to collectively help those people. Nothing wrong with that. I do have a problem supporting the moron who has a Double Big-Gulp every day chased by a large pizza and no exercise other than playing XBox for hours every day. That said, the app for the model looks interesting. I had my basal metabolic rate measured last year before I started a Master's Swimming program. I like numbers and wanted to have some data. It was 1850 kcal/day. According to the Human Weight Simulator I have to consume 2576 kcal/day to maintain my weight. That, for some reason, feels way too high. I haven't counted calories in a long time, but might do it for a few weeks just to get a sense of what this model is doing. I doubt that I am consuming much more than 1700 kcal/day on average. But, I could be wrong. I'd be nice if they released a paper with this equation the article mentions. Is that published anywhere?
nazgulnarsil 14y ago
sugary drinks. I've never known someone to drop these and not lose weight. It is SO EASY to consume an extra 500 calories a day of liquid sugar. It has close to zero satiety. A 500 calorie surplus is a pound of weight gain a week.
- deleted 14y ago
  [deleted]
- jrockway 14y ago
  I gave up sugar a few years ago and there was pretty much no effect. I didn't have much sugar before, and there are plenty of other sources of calories.
  - nopassrecover 14y ago
    Yeah likewise. I almost never have a sugary drink (maybe a softdrink can once every 3 months) and it's made zero difference to weight. Stress on the other hand is highly correlated personally with weight (I've lost ~10kg in 3 months every time I've quit a job).
    - nazgulnarsil 14y ago
      wtf guys obviously if you didn't drink a lot of this stuff before then losing it will have a correspondingly small effect. Calories in calories out.
      - derleth 14y ago
        > Calories in calories out. Every time someone says that, the people with a hobby-horse to ride come out and beat on the person for a bit. Especially if they imply that honey (no, sorry, the correct term now is HFCS) isn't the Devil's own temptation sent to corrupt and impurify our precious bodily fluids.
        jrockway 14y ago
Pressenter 14y ago
These articles are so amusing. As a regular cyclist eating too much has never been a problem for me. If people really wanted to be thin they would get their ass out on the bike trail with the rest of us ridiculously fit people instead of sitting in front of the television. Since its pretty lonely out there most of the time its clear what choice people are making and I don't feel one bit sorry for you when you have to live with it. Fatty.
koeselitz 14y ago
"Well, what do people do when there is extra food around? They eat it! This, of course, is a tremendously controversial idea. However, the model shows that increase in food more than explains the increase in weight." This doesn't actually follow logically. I know Mr Chow is implying that there's a lot of data that this interview obviously doesn't present, but there are serious problems with this thesis on the face of it. For one thing, if obesity correlates directly with the availability of food, then the most obese people ought to be those to whom food is most available. But the rich in our society are proportionally not as obese as those who face periodic food shortages; and low-income children are proportionally shown to be at much higher risk of suffering from obesity. [1] Not only that, but the statement that food production has simply gone up and therefore food prices have simply gone down is incredibly... simplistic. There have been arguments for years [2] about what food prices have gone down or up and how that may or may not have affected obesity. I want to believe that there's data behind this fellow's claims, but I can't help but feel as though, no matter what the data is, summarizing it in the way he does is deceptive. [1] http://jama.jamanetwork.com/article.aspx?volume=303&issue=1&page=2 http://jama.jamanetwork.com/article.aspx?volume=303&issu... [2] For example, http://www.good.is/post/the-inconvenient-truth-about-cheap-food-and-obesity-it-s-not-farm-subsidies/ http://www.good.is/post/the-inconvenient-truth-about-cheap-f...
- notJim 14y ago
  I, too, am skeptical of that thesis. However one plausible way of thinking about it may be that because food prices are so low (for certain foods, at least), restaurants can increase portion sizes without incurring a very high penalty. If people are attracted to higher portion sizes, then those restaurants would continue to do so, resulting in fat people. I can think of a couple of reasons that people would like larger portion sizes: a) it improves the value-proposition ($x amount of food for just $y dollars), and b) it is satisfying to feel full. Your point about the rich is an interesting one. A conceivable explanation for this could be that higher-end restaurants tend to have a different value-proposition than lower-end ones: instead of focusing on quantity, they focus on quality. Finally, I think the point you bring up about the summary being misleading is a good one. Reporters are generally not known for accuracy when reporting on scientific matters.
- 14y ago
optymizer 14y ago
if someone else is having problems launching their Java Applet, but you have Java installed, download the jar from: http://bwsimulator.niddk.nih.gov/WeightAppletv10.4.6.signed.jar http://bwsimulator.niddk.nih.gov/WeightAppletv10.4.6.signed.... then run the following command: java -cp WeightAppletv10.4.6.signed.jar weightapplet.MainPanel
dbecker 14y ago
I was unable to find original source material by the researcher (only finding the abstract for his presentation at http://aaas.confex.com/aaas/2012/webprogram/Paper6155.html http://aaas.confex.com/aaas/2012/webprogram/Paper6155.html) If anyone can find the author's slides or related article, I'd appreciate a link to them.
- notJim 14y ago
  This is the obesity section of the author's website: http://sciencehouse.wordpress.com/category/medicine/obesity/ http://sciencehouse.wordpress.com/category/medicine/obesity/ He links to the slides from that conference: http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf

101 points by ckuehne 14y ago

"An extra 10 calories a day puts more weight onto an obese person than on a thinner one." It needs to be explained how he determined that this isn't related to _why_ they are obese in the first place, i.e. whether these are purely correlational facts. It would be nice if the New York Times wasn't susceptible to elementary statistical fallacies like this but... well this is nutrition after all.

streptomycin 14y ago
An interview in the New York Times is not an academic research paper. In this context, it's reasonable for the interviewer to take the mathematician's word for it rather than hammering away at a pedantic detail that may or may not be relevant.
- Almaviva 14y ago
  This would be reasonable if people who ought to know better didn't commit this kind of elementary error constantly, particularly in nutrition. It is your attitude, that it's reasonable to publish a scientific article in a major publication without independent thought and fact checking, that I am challenging.
  - scott_s 14y ago
    it's reasonable to publish a scientific article in a major publication without independent thought and fact checking The person you are replying to did not say or imply that.
howeyc 14y ago
There was a documentary on HBO recently that stated this as well. What's going on is that someone who is obese needs less calories per day to maintain their weight than someone who is not obese. Something to do with metabolism rates slowing down when you are overweight. See "Weight of the nation."
- colomon 14y ago
  Except that's completely backwards to any "calories needed" calculation I've ever heard before. For instance, I just tried http://caloriecount.about.com/cc/calories-goal.php http://caloriecount.about.com/cc/calories-goal.php (after googling it out of the blue) with starting weights of 300 and 200, ten pounds to lose both ways, everything else the same. The calculator suggested the 200 pound guy needed to eat 500 calories a day fewer than the 300 pound guy did.
  - waterlesscloud 14y ago
    It's just a calculator on the internet, based on some simple formula. If experimental data says otherwise, the calculator is simply wrong.
    - drostie 14y ago
      While this is true, it is not particularly enlightening. The problem is that earlier a definite assertion was made that obese people burn fewer calories per day when staying at the same weight, and colomon was saying that this is known to be contradicted by certain experimental facts. It is known from experiment that basal metabolic rates are larger as your weight goes up. It's even consistent with a simple causal model. Obese people have larger bodies, which require more maintenance -- a larger supply of blood vessels and a heart working harder to fill them, more energy expended in getting up and going to the bathroom, et cetera. So it's kind of "no mystery." Now, it might still be the case that this documentary was correct -- for example, while basal rates might be higher for obese people, perhaps normal-weight people simply have an exercise routine which increases their metabolism in general. Something like that would be useful and would help colomon understand why the result is backwards. Unfortunately, I didn't see the documentary and therefore I don't know this particular reason, but the question is legitimate and is not well-dismissed simply by saying, "oh you know that crazy internet."
    - whatusername 14y ago
      So the Hans Benedict formula (which has been in use since 1919) is directly weight related. The Katch-McArdle and Cunningham try to be more specific and relate to the Lean Body Mass (LBM). However -- since LBM is reasonably correlated with overall weight -- then we can assume that (all else being equal) the fatter person has a higher BMR.
Wilduck 14y ago
Thanks for bringing this up, I'd really like some statistical awareness to show up in science reporting. > It needs to be explained how he determined that this isn't related to _why_ they are obese in the first place, i.e. whether these are purely correlational facts. I would settle for a simple statement that "An extra 10 calories a day puts more weight onto an obese person than on a thinner one," all else equal or controlling for other factors. So much of science is based off accepting statistical evidence, that it would be invaluable for science reporting to state, at least in laymans terms, the statistical veracity of results. In this case such a statement should be even easier since we're dealing with a theoretical model of obesity. Is there a coefficient for "current weight" that is independent of other factors?
byoung2 14y ago
It needs to be explained how he determined that this isn't related to _why_ they are obese in the first place I agree that more explanation is needed...the thinner person may be thin because she is more active, and the obese person may be obese because she is more sedentary. An extra 10 calories would seem more likely to put more weight on a sedentary person than an active one.
- glenra 14y ago
  The reverse claim has just as much explanatory power. That is to say: The active person may be active because she is more thin, and the sedentary person may be sedentary because she is more obese.
dbecker 14y ago
I've only flipped through this so far, which obviously isn't enough to fully grasp the argument. But you can find the researcher's reasoning explained in his slides at : http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf

opiumden 14y ago

It's nice to see that people are developing new models and ways of thinking about weight loss but I wonder how effective this research is going to be. The conclusion of the article is the same old "eat less and eat healthier" which is fantastic advice ... and advice that a great many people don't bother to follow. As a culture we're eating ourselves to death while worrying that low probability events like terrorist attacks are going to kill us. We're killing us and we're doing it slowly.

Retric 14y ago
Well, stop subsidizing farmers is probably a good takeaway.
- jrockway 14y ago
  I doubt anyone is getting fat from raw whole foods.
  - Drbble 14y ago
    Farm subsidies are largely for corn products and for non-production of overproduced commodities.
potatolicious 14y ago
> "which is fantastic advice ... and advice that a great many people don't bother to follow" At least a large part of this is due to lack of education. For all the time we spend on math and science in public schools, we spend none of it on some basic principles like nutrition. I was rather obese in high school, and the (Canadian) government foot the bill for nutrition courses and consultations with a dietitian (this is a big can 'o worms too: preventative programs like this are way easier in a single-payer system). I now have the ability to judge what's good for me, and what isn't, as well as effective alternatives to existing choices. That knowledge has been instrumental in my weight loss. The problem with that "fantastic advice" is that it's rarely coupled with real constructive suggestions. "Eat less and eat healthier, fatass" is unproductive when the person lacks the knowledge to make effective choices, and alternatives to break entrenched habits aren't presented. Sure, a Big Mac is universally unhealthy, but what do you replace it with? A grilled cheese sandwich isn't much better, nor are a lot of "healthier looking" alternatives (anything with mayo slathered in it is dietary suicide, regardless of how much greens you stick in it also). How do you curb hunger when in the process of downsizing your portions? Curling up in a corner isn't super effective. Blood sugar management throughout the day to get you through the rough patches? None of this is trivial knowledge. Of course, the factor making all of this substantially worse is that the signal to noise ratio in dietary literature is horrific. For every real, researched book on effective diets, you have 3 more fad diets backed up by voodoo and pseudoscience.

brd 14y ago

The Omnivore's Dilemma (Michael Pollan) goes into more detail on the history of the food boom in the 1970s and its link to obesity. Its a great read for anyone interested. Essentially we got hit with a one-two punch of food price paranoia and the high fructose corn syrup innovation.

saddino 14y ago
I'd also recommend The End of Overeating (David Kessler) which posits that the obesity explosion is due to recent advances in food science re: foods engineered (precise ratios of fat, sugar and salt) to make you want to eat more ("conditioned hypereating"). If you want to lose weight, stop eating packaged food, cut out fast-food and cut back on restaurants/take-out. Make your own food (like everyone did 40 years ago for most meals) and you'll find yourself controlling your portion intake by default.
- wpietri 14y ago
  I second that. In April I tried an experiment: home-cooked meals at least twice a day, and nothing with a human-boosted glycemic load. E.g., nothing with added sugar, no refined carbs, no fruit juice. Portion control was much, much easier. I still ate until I felt full; I just felt full a lot sooner, and experienced a big drop in between-meal cravings.
- deleted 14y ago
  [deleted]

csmeder 14y ago

"What caused the obesity epidemic?" "And it’s something very simple, very obvious, something that few want to hear: The epidemic was caused by the overproduction of food in the United States. ...This, of course, is a tremendously controversial idea. However, the model shows that increase in food more than explains the increase in weight." This is analogous to saying: "What caused the increase in car accidents?" "And it’s something very simple, very obvious, something that few want to hear: The car accident epidemic was caused by the overproduction of cars in the United States. ...This, of course, is a tremendously controversial idea. However, the model shows that increase in cars more than explains the increase in car accidents." By using the phrase "overproduction of food" he is using too broad of a statement that doesn't describe the problem in an addressable way. It makes it sound like we could just cut food production across the board and prevent obesity. . I would argue the problem isn't the quantity, rather the quality. Quality in regards to: - Nutrients vs Fat and sugars - Number of meals a day and the time we eat those meals - Sugary drinks vs Water - Appropriate meal size - Fast food vs home made meals The solution for the 21st century is going to take more than cutting food production. Just as curbing injuries from car accidents will take a different approach than limiting US car production.

alexandros 14y ago
> I would argue the problem isn't the quantity, rather the quality But you didn't, argue. You simply asserted. You threw out the article's theory by constructing a straw-man you didn't even bother tearing down, then proceeded to inform us of your views.
- aMoniker 14y ago
  Actually, he said that he 'would' argue. So he is not actually arguing, but informing us that if necessary, an argument could be constructed based on the view he presented.
- brady747 14y ago
  You are right, but he didn't say he was arguing in his comment, he said he would. :)

mhartl 14y ago

You are an M.I.T.-trained mathematician and physicist. How did you come to work on obesity? ...I didn’t even know what a calorie was. I call bullshit.

theorique 14y ago
Exaggeration for effect? It's perfectly plausible that a mathematician / physicist would have a weak layman's understanding of energy balance in nutrition.
- mhartl 14y ago
  You're probably right. Maybe in an audio interview the irony would have come through.
eugenejen 14y ago
Why do you say it as bullshit? One important thing in higher education for math and physics is to be able to perform detail technical computations or modeling for phenomenons. In common high school and undergraduate physics class, it only requires students to be able to come up models with intuitions. But in graduate schools, you are trained to examine each step to make sure nothing is left out or based on assumptions that are wrong in your mind. Therefore a lot of time you are not sure what something is until you re-examine all postulates that you learn when you are young.
- kalid 14y ago
  > Why do you say it as bullshit? An MIT-trained physicist should know the common name for a unit of energy. Sure, he might not remember the conversion from joules to calories, but to have never heard of it? That's taking a literal reading ("I didn't know what a calorie was"), but perhaps he was referring to a more nuanced understanding ("I didn't understand how energy was used by the body"). That interpretation wasn't clear from the text though -- it seemed an overwrought attempt to portray an "Aw shucks, I didn't know what I was doing!" attitude.

vsviridov 14y ago

tl;dr - eat less

lukifer 14y ago

Math alone is the wrong tool to solve a problem that is biochemical and behavioral in nature. On an individual level, the fix is straight-forward: eat more "good" fats, and little or no grains and sugars. I have yet to encounter someone who has done this and not seen dramatic results. It's a trickier problem on a broad sociological level, though. The sugar peddlers have an incentive to create and maintain the addiction, and yet they're also just giving people what they want, and at the end of the day, it's still a free country. We can't ever expect all people to abandon sugar any more than all people have abandoned smoking. As much as I hate to agree with libertarian dogma, I think the USDA is a big part of the problem. They've been been promoting high-carb diets and "moderate" sugar consumption for decades, and it certainly smells like yet another government-industrial complex protecting existing profits.

ticks 14y ago
Those high-carb diets were probably useful several decades ago, especially in countries that suffered from the world wars. I think it had good intentions but due to those commercial influences, the advice wasn't adapted to fit modern lifestyles.
zkirill 14y ago
>> eat more "good" fats, and little or no grains and sugars. Grains, specifically cereal grains, may serve as a limited dietary source of fiber, essential amino acids, vitamins, and minerals. As with everything, it is best to exercise moderation but I wouldn't recommend fully removing grains from the diet. Refined (table) sugar is a common offender but small dosages of fructose and sucrose from a daily serving of fresh fruits and vegetables are justifiable.
- sliverstorm 14y ago
  Oats are a grain, and I've never heard anything but praise for oats, from anyone. Such things as russet potatoes are probably more questionable than oats, for example, as I believe they are almost entirely starch.
  - 14y ago

its_so_on 14y ago

I disagree with the article, and don't believe mathematics has the answer to obesity. However, if someone would like to start a diet-centered startup with me, I believe I have an insight that invalidates every diet book on the planet. Every diet book on the planet makes one very false assumption. Before we get to the assumption, let's review something uncontroversial: - You put on fat by eating more calories than you use; and you lose fat by using more calories than you eat. In other words, losing fat (beating obesity) would seem to be a combination of "diet and fitness". If you like, you can view every diet book on the planet as a combination of strategies that fall into those two categories (eat less or use more of the calories). So how can ALL those strategies be wrong? Let's turn the equation "net fat gain = calories in - calories out" into something more familiar. "net bank account gain = money in - money out." is it really so simple? Yes. Everyone who weighs more than they want has more money in their bank account (more Calories on their body, ready to burn off) than they want. Now to get to the big diet books' fallacy, let's turn this around. You're a multimillionaire and want to lose half of your money. What's the easiest way to do it? The easiest way to do it, if you're a millionaire, is to call up your accountant and say, "I would like to donate half of my money to Bill and Melinda Gates foundation, please arrange this." That's a strategy. You can write it down on a piece of paper and fax it to your accountant with your signature on the bottom, after a few more signatures it's done. So, what is the difference between THIS strategy and a DIET strategy? Simple: When you wrote that down to fax your your accountant (or booked a hotel room by email, or booked an appointment with a repairperson, contractor, whatever, basically anything like that) then the strategy you wrote down and faxed, in that fax, had the effect that the person it addresses WILL OBEY YOUR COMMAND. They will follow your strategy. Whereas, if you decide "every morning 5 pushups" and write it down, even if you fax it to yourself that does NOT mean that its recipient (you) will do 5 pushups the next morning. In other words, every diet book on the planet thinks that you are the boss of the person doing the dieting and exercising, and simply have to micromanage what they do. But you are NOT the boss of you. Let's recap. Writing: "Dear ---, After careful deliberation I have decided that I will immediately be donating 1/2 of all of my wealth to the Bill and Melinda Gates foundation. Please liquidate an appropriate portion of my investments in stocks, bonds, and mutual funds (in equal measure) for me to to be able to donate half of my net worth, and then prepare the donation for my signature. Yours truly," now it will start to happen, and another signature or two and it's done. (Even if this was considerable work for the accountant!!!) Now write down: "Starting tomorrow morning, as soon as you wake up please ensure your first action is to do 5 pushups and 5 situps. For seven days do so, then for the next week do 10 of each, the next week 15 of each, then 20, and os on, until you reach 50 of each (after 10 weeks), which you should keep doing indefinitely. Yours truly, yours truly." Simple strategy, right? Only problem is, if you fax it to yourself, I can almost guarantee you that the recipient of the fax will not do what you want. Even if you sign it. Even if you really, really want you recipient to follow through. They won't. Every single diet book makes the SINGULAR mistake of thinking that its reader is free to choose a strategy of consumption and of exercise. Not so: the reader can agree with every word. Unlike agreeing with every word of investment advice that a rich person can order an accountant to follow through on, the reader of any diet book has no such power to order that a strategy (of either diet or of exercise) be executed. - read about Tahiti, decide you want to see it, call your travel agent and have them book a room in Tahiti, and a room will be booked in Tahiti. - read a fad diet, decide you want to see the results, and... no guarantee you will have a chance to see them. In sum, if you see what is wrong with the present offering, please email me for collobaring on an interesting alternative.

paul-woolcock 14y ago

The "calories in/calories out" argument is based on the assumption that the human body is a closed system. This is simply not the case, and touting it as a diet strategy is irresponsible. You might lose weight if you lower your caloric intake by only eating 1 McDonalds cheeseburger a day instead of 2, but in the end you are still eating crap food "product", and you won't be as healthy as you could be by focusing on the _quality_ of your food as opposed to the _quantity_.

robomartin 14y ago
Well, there's loosing weight and loosing body fat. Two very different things. Two visibly different things.
getsat 14y ago
There's a few National Institute of Health studies that back the calories in vs calories out argument. Keep your calorie intake below your BMR (basal metabolic rate) + what you burn during the day if you want to lose weight. Very simple. You don't have to "balance saturated and unsatured fats", get ten hours of sleep per day, or whatever other ridiculous microoptimisations people come up with. Eat 500 calories below your MBR + burn rate and you lose one pound per week. You can do it while eating garbage food (fast food, heavily processed food products) or you could do it while eating a totally vegan diet. It doesn't matter for weight loss.
- Drbble 14y ago
  Look up "compliance" and how it relates to self-applied medical care for nutrition, acne, exercise, birth control, etc. Vasectomy is more effective than pill is more effective than condom, not because of chemistry or biology or physics, but because of psychology.
- paul-woolcock 14y ago
  That makes sense. I suppose I just think of something different than I should when I hear "weight loss." When someone says "weight loss," I hear "body composition change," which is obviously different than weight loss.

robomartin 14y ago

"And it’s something very simple, very obvious, something that few want to hear: The epidemic was caused by the overproduction of food in the United States." Overproduction? Does a factory intentionally produce more cars than it can sell? Probably not. How about a baker? Does a baker produce more cookies than she can sell? Not for long. Maybe a farmer? No. Not really. That is not an economically sustainable position to take. If we take the "overproduction" assertion as fact, this begs the question: Why is this happening? One answer is that consumers have more money to spend and they are choosing to spend some of it buying (and consuming) more food. Fair enough. Another answer could be that, in certain segments, government geniuses decided they know better than to let free market work. They go in and throw money around to make producers do what they would not under normal circumstances. That triggers over-production of certain goods. Which triggers lower prices. Which triggers higher consumption. And so on. Another possible answer is a combination of the above. I am, admittedly, against government meddling in our lives. I want them out of nearly everything. Go throw parties for foreign dignitaries and balance our books. Maybe do a few more things. Oh, yes, those borders. Deal with them will ya? Any time these guys dip their ignorant toes into the water of our lives they invariably create a mess that our children and our children's children will have to pay for. Of course, this philosophy extends to self-responsibility. In my family we might have a soft drink or two at parties here and there. Just like having ice-cream, in moderation it is an occasional treat. Aside from that, water only. What the hell is wrong with people that go into a gas station and order a 64 ounce soft drink? That's like consuming a cup full of sugar while you drive to work. This is where another angle in this equation comes into play: A third-payer system of health does not penalize bad behavior. Someone who is a complete moron when it comes to how they take care of their bodies and what they put into it should suffer the financial consequence of having to pay a lot more for healthcare. Today, those of us who try to be sensible are paying for the idiots who are not. That is fundamentally wrong. If you want a healthy and slim population, again, get government the hell out of the way. Yes, it can be that simple. Don't manipulate markets and don't get involved in healthcare. People should buy and pay for their own health insurance, just like they do car insurance. If you drive like a mad-man and get tickets and accidents your insurance goes up or it could be cancelled. The end result is that people modify their behavior to what is a financially sensible state. The same would happen with healthcare if people were directly responsible for their own insurance and suffered the consequences of their dumb decisions. Smoke and destroyed your lungs? Your insurance should cost you $50K per year. Enjoy. Drink alcohol like an animal and turned your liver into mush? $75K a year. Have fun. The rest of us would have sensible policies which would reward us for being responsible while covering us in the case of catastrophic events or serious illness outside of our control. To be clear, I don't have a problem contributing to the pot to help out those afflicted with cancer or similar horrible diseases. A portion of everyone's premiums would cover these out-of-the-norm cases. Then there's the case of obesity caused by diseases like Cushings Syndrome (pituitary gland tumor) that's potentially deadly and has nothing to do with over-eating. We need to collectively help those people. Nothing wrong with that. I do have a problem supporting the moron who has a Double Big-Gulp every day chased by a large pizza and no exercise other than playing XBox for hours every day. That said, the app for the model looks interesting. I had my basal metabolic rate measured last year before I started a Master's Swimming program. I like numbers and wanted to have some data. It was 1850 kcal/day. According to the Human Weight Simulator I have to consume 2576 kcal/day to maintain my weight. That, for some reason, feels way too high. I haven't counted calories in a long time, but might do it for a few weeks just to get a sense of what this model is doing. I doubt that I am consuming much more than 1700 kcal/day on average. But, I could be wrong. I'd be nice if they released a paper with this equation the article mentions. Is that published anywhere?

nazgulnarsil 14y ago

sugary drinks. I've never known someone to drop these and not lose weight. It is SO EASY to consume an extra 500 calories a day of liquid sugar. It has close to zero satiety. A 500 calorie surplus is a pound of weight gain a week.

deleted 14y ago
[deleted]
jrockway 14y ago
I gave up sugar a few years ago and there was pretty much no effect. I didn't have much sugar before, and there are plenty of other sources of calories.
- nopassrecover 14y ago
  Yeah likewise. I almost never have a sugary drink (maybe a softdrink can once every 3 months) and it's made zero difference to weight. Stress on the other hand is highly correlated personally with weight (I've lost ~10kg in 3 months every time I've quit a job).
  - nazgulnarsil 14y ago
    wtf guys obviously if you didn't drink a lot of this stuff before then losing it will have a correspondingly small effect. Calories in calories out.
    - derleth 14y ago
      > Calories in calories out. Every time someone says that, the people with a hobby-horse to ride come out and beat on the person for a bit. Especially if they imply that honey (no, sorry, the correct term now is HFCS) isn't the Devil's own temptation sent to corrupt and impurify our precious bodily fluids.
      - jrockway 14y ago

Pressenter 14y ago

These articles are so amusing. As a regular cyclist eating too much has never been a problem for me. If people really wanted to be thin they would get their ass out on the bike trail with the rest of us ridiculously fit people instead of sitting in front of the television. Since its pretty lonely out there most of the time its clear what choice people are making and I don't feel one bit sorry for you when you have to live with it. Fatty.

koeselitz 14y ago

"Well, what do people do when there is extra food around? They eat it! This, of course, is a tremendously controversial idea. However, the model shows that increase in food more than explains the increase in weight." This doesn't actually follow logically. I know Mr Chow is implying that there's a lot of data that this interview obviously doesn't present, but there are serious problems with this thesis on the face of it. For one thing, if obesity correlates directly with the availability of food, then the most obese people ought to be those to whom food is most available. But the rich in our society are proportionally not as obese as those who face periodic food shortages; and low-income children are proportionally shown to be at much higher risk of suffering from obesity. [1] Not only that, but the statement that food production has simply gone up and therefore food prices have simply gone down is incredibly... simplistic. There have been arguments for years [2] about what food prices have gone down or up and how that may or may not have affected obesity. I want to believe that there's data behind this fellow's claims, but I can't help but feel as though, no matter what the data is, summarizing it in the way he does is deceptive. [1] http://jama.jamanetwork.com/article.aspx?volume=303&issue=1&page=2 http://jama.jamanetwork.com/article.aspx?volume=303&issu... [2] For example, http://www.good.is/post/the-inconvenient-truth-about-cheap-food-and-obesity-it-s-not-farm-subsidies/ http://www.good.is/post/the-inconvenient-truth-about-cheap-f...

notJim 14y ago
I, too, am skeptical of that thesis. However one plausible way of thinking about it may be that because food prices are so low (for certain foods, at least), restaurants can increase portion sizes without incurring a very high penalty. If people are attracted to higher portion sizes, then those restaurants would continue to do so, resulting in fat people. I can think of a couple of reasons that people would like larger portion sizes: a) it improves the value-proposition ($x amount of food for just $y dollars), and b) it is satisfying to feel full. Your point about the rich is an interesting one. A conceivable explanation for this could be that higher-end restaurants tend to have a different value-proposition than lower-end ones: instead of focusing on quantity, they focus on quality. Finally, I think the point you bring up about the summary being misleading is a good one. Reporters are generally not known for accuracy when reporting on scientific matters.
14y ago

optymizer 14y ago

if someone else is having problems launching their Java Applet, but you have Java installed, download the jar from: http://bwsimulator.niddk.nih.gov/WeightAppletv10.4.6.signed.jar http://bwsimulator.niddk.nih.gov/WeightAppletv10.4.6.signed.... then run the following command: java -cp WeightAppletv10.4.6.signed.jar weightapplet.MainPanel

dbecker 14y ago

I was unable to find original source material by the researcher (only finding the abstract for his presentation at http://aaas.confex.com/aaas/2012/webprogram/Paper6155.html http://aaas.confex.com/aaas/2012/webprogram/Paper6155.html) If anyone can find the author's slides or related article, I'd appreciate a link to them.

notJim 14y ago
This is the obesity section of the author's website: http://sciencehouse.wordpress.com/category/medicine/obesity/ http://sciencehouse.wordpress.com/category/medicine/obesity/ He links to the slides from that conference: http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf http://sciencehouse.files.wordpress.com/2012/02/aaas122.pdf