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Math Science

The Mathematics of Obesity 655

Hugh Pickens writes "The NY Times reports that Carson C. Chow, an MIT-trained mathematician and physicist, has taken a new look at America's obesity epidemic and found that a food glut is behind America's weight problem, with the national obesity rate jumping from 20 percent to over 30 percent since 1970. 'Beginning in the 1970s, there was a change in national agricultural policy. Instead of the government paying farmers not to engage in full production, as was the practice, they were encouraged to grow as much food as they could,' says Chow. 'With such a huge food supply, food marketing got better and restaurants got cheaper. The low cost of food fueled the growth of the fast-food industry. If food were expensive, you couldn't have fast food.' Chow and mathematical physiologist Kevin Hall created a mathematical model of a human with hundreds of equations, boiled it down to one simple equation, and then plugged in all the variables — height, weight, food intake, exercise. The slimmed-down equation proved to be a useful platform for answering a host of questions. For example, huge variations in your daily food intake will not cause variations in weight, as long as your average food intake over a year is about the same. Unfortunately, another finding is that weight change, up or down, takes a very, very long time. Chow has posted an interactive version of the model on the web where people can plug in their information and learn how much they'll need to reduce their intake and increase their activity to lose."
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The Mathematics of Obesity

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  • by Krneki ( 1192201 ) on Wednesday May 16, 2012 @05:28AM (#40014299)
    The main problem is sugar.

    It's everywhere and you don't need it. Drink only water and don't buy any food that has sugar (fructose excluded) in it.

    You DON'T need it. You like it because your are an addicted junky.

  • by Shivetya ( 243324 ) on Wednesday May 16, 2012 @05:52AM (#40014385) Homepage Journal

    Far too many Americans are simply not active. This is compounded by the fact that while not active they have easy access to food that it too conveniently packaged for consumption. I love the people at work who blame medical conditions for their weight while consuming a whole bag of chips or having that bagel covered in cream cheese. People don't know the calories they are consuming and woefully underestimate the amount of them in the foods they eat.

    So sugar is only part of the problem. I know lots of people who don't eat cookies, drink soda, or the like, and yet they little walking cubed shaped individuals. All because of the mass amount of carb and fat filled foods they consume.

    Gone are the long days and long weeks of manual labor. Instead most Americans sit during their workday and spend only a third of their week at most working and traveling too and from work. I am not declaring that working only forty hours or less is bad; but lets be honest those we know who do more tend to get further; but it did leave many people with way too much time on their hands and they don't know what to do with it.

    You can maintain a healthy weight and eat some truly trashy food. As part of a diet and exercise contest we have at work I set out to prove that some seriously trashy breakfast foods could be consumed while losing weight as long as the diet and exercise balanced out. This meant items like donuts or muffins with coffee and cream from Dunkin in the morning every work day for two weeks. Yet followed by sensible lunches and dinners which most of us kept logs for. Those who logged their food showed the most loss. That is the real key, knowing what you eat.

  • by sco08y ( 615665 ) on Wednesday May 16, 2012 @06:01AM (#40014429)

    Just so we can get them out of the way:

    "I tried diet X and lost Y pounds, thus clearly establishing that substance Z is causing everyone to become fat."

    "Moral failing Q is the real culprit! We need government policy R! I have no proof!"

    "I'm from country C and we have no fat people. You Americans are fat, and I have a ridiculous accent!"

  • Re:long time? (Score:4, Informative)

    by ghostdoc ( 1235612 ) on Wednesday May 16, 2012 @06:19AM (#40014487)

    of course, if you exercise as part of the lifestyle change, you'll be putting on muscle, which weighs a lot more than the fat you're losing.

    I've just run the simulator in TFA on my known variables for the last year (I got diagnosed with type 2 diabetes and had to make some very controlled, measured, changes to my lifestyle which got me back to being healthy).
    It said I'd have lost over 30Kg over that year. I actually lost just under 10Kg, but went from being unable to run for more than 100m to completing a 12Km fun-run and confidently entering for a half-marathon in 3 months' time. I also lost about 6inches off my waistline (as in I gained a waist!).

    Also, humans are not controlled by variables and equations. The equations describe an average person, who doesn't exist. They're useful approximations, but in the end just approximations.

  • Re:Drugs (Score:5, Informative)

    by Lumpy ( 12016 ) on Wednesday May 16, 2012 @06:28AM (#40014523) Homepage

    Baking your own bread makes HUGE changes in diet. Most bread in the store has a metric buttload of sugars added simply because they can. home made bread has t he minimum needed and it is usually consumed by the yeast.

    Want to make that baked bread better? slow rise in the fridge overnight. the yeast will consumer more sugars and add in a lot more flavors. Sourdoughs are the best for you.

  • by transporter_ii ( 986545 ) on Wednesday May 16, 2012 @07:30AM (#40014919) Homepage

    Other factors factored in, like activity, Campbell found surprisingly that many Chinese actually consume about 30% more calories than Americans, yet they had incredibly less overweight people. Again, he didn't compare a sedentary American to a field worker in China, he compared them to an office worker in China to make it fair.

    So it wasn't just calories, it is the types of food. Processed foods and animal foods are to blame. China actually proves to be an excellent place to study because they have a wide range of groups that live the same way, eat the same way, and live in the same place most of their lives. Campbell found that the more animal foods and processed foods they ate, the more disease and obesity the had. This isn't just junk science, either. You can do the research for yourself. As third world countries get wealthier and adopt a western-style diet, they also adopt western disease rates and obesity. It is not just their genes. If they move here and start eating like us, they get our diseases at the same rates (or higher). There is nothing special about these people other than their diets.

    Our diets combined with our lifestyles are killing us here...and if you want to cut your chances of cancer, diabetes, and other chronic illnesses down, the solution is simple. All you have to do is eat like you live in a 3rd world country. Less animal products and processed foods, more whole foods. It's that simple.

    I do disagree with Campbell that you *have* to become a vegetarian. They do eat meat in China, just way less of it. But his studies on people that reversed massive heart disease just by becoming vegetarians is fairly impressive.

  • by AbRASiON ( 589899 ) * on Wednesday May 16, 2012 @07:33AM (#40014943) Journal

    I think I found this here like 5 years ago and I've kept it since. []

    I've emailed Richard last year by the way and he's still the weight he achieved in that article 9 years later.

    FWIW: I'm an endomorph who DOES believe that some people hold weight easier, crave carbs and sugar more than others and have a lower BMR. However science is science - these things only make up a small fraction of the work. 95%+ is simply putting in the effort.

    I can also confirm that adjusting diet is far, far far more rewarding than excercise for weight loss, despite other health benefits. Just as his article says.

  • I eat Paleo (Score:2, Informative)

    by Anonymous Coward on Wednesday May 16, 2012 @07:33AM (#40014947)

    Lots of meat, almost NO carbs (under 50g a day) tons of green veggies. Lost 11 lb in the first week and around 5 lb/week afterward. I will reach my and since I cook all the stuff I eat, maintenance is easy since good habits are now a given. Grok on!

  • by Bongo ( 13261 ) on Wednesday May 16, 2012 @07:52AM (#40015093)

    The energy balance equation of, food eaten equals fat stored minus exercise, is used in a very misleading way. Most assume you can manipulate it yourself by eating less and exercising more. But that ignores entirely the body's own control system. There are some lab rats that were starved to death by underfeeding, in an experiment, and whilst they starved to death they were gaining fat and died obese. Why? Because they were also receiving insulin and this told their bodies to store fat no matter what, even if they were not being fed, so they converted their muscle and organs into fat and stored that instead. They died of weak heart mucles and heart failure.

    It is like a child eats extra to grow but he doesn't grow because he's eating extra, he eats extra and grows because the body's hormones are controlling things and telling the body to eat more and grow. It is all about hormones. Why do diabetics take insulin? To CONTROL their blood sugar. That's what insulin does. Insulin decides that you have to lower that blood sugar. And how does it control it and get it out of the blood stream? It tells fat cells to open up and absorb it. That's what "lowers" your blood sugar. The insulin decides to store it. And as it is storing it, your normal metabolism is still hungry. So the energy equation is used wrong. You don't get fat because you overeat, you overeat because you're getting fat.

    What drives up insulin levels beyond normal, beyond what our 100,000 year old bodies are used to? Carbohydrates. You can eat fat and that'll be converted to energy and you'll want to move more. But eat carbs in the massive unusual quantities that we do, like pasta, pizza, bread, potatoes, and sugared drinks, and it all turns to sugar and insulin has to be produced in huge quantities to deal with it. Your normal blood sugar is one teaspoon of sugar. That's it. That's all we're made to deal with. So insulin goes nuts trying to deal with all that "healthy slow release energy" and eventually you get obese and you get diabetes.

    The food pyramid was a huge shift towards grains (bird food) and away from fat. The fat / heart disease / lipid hypothesis was wrong 50 years ago and by committee "we have to tell the politicians what to regulate even if we aren't sure ourselves" consensus opinion ended up dominating and it is still wrong today. Eating a low fat high carb diet is a recipe not only for obesity but also depression. Just try switching to a genuine low carb high fat diet (see Sweden's latest magazine, "LCHF") and try it for yourself. After a month carbs just don't look like food anymore. Sleep better, feel lighter, feel satiated all the time (fat is filling, whilst carbs increase appetite or make you sleepy) and have more mental clarity. YMMV but that's been my experience to my surprise.

    There are so many things wrong with the current dogma around the food pyramid that you have to undo many issues before you can wade your way to some clarity. But the best thing is to actually try it for a period, and see if what the proponents of LCHF and paleo say is true. Your own body can tell you.

    Go and check what that research about bad fat and heart disease was actually based on, how they've repeatedly failed to show in good controlled studies that eating low fat is good for you, or that counting calories and exercising lets you lose wight. Those studies keep failing but the advocates keep hoping the next big study will show it. The start in rise in obesity coincided with the start of that advice about fat being the devil and to make most of your food plate carbs (sugar) instead. It has been a massive experiment on the public and it has gone catastrophically wrong, but rather than say that they just call people weak willed and lazy. All those carbs and sugar simply drive up your hunger whilst storing it as fat and keeping you tired.

  • by transporter_ii ( 986545 ) on Wednesday May 16, 2012 @08:04AM (#40015177) Homepage

    Here is the same info from the Lancet. Per wikipedia, the Lancet is "one of the world's best known, oldest, and most respected general medical journals."

    Cross off cancer here and insert diabetes, or obesity. If you bothered to do your own research, I guarantee you could could not just dismiss this as bullshit.

    From the Lancet:

    "In many [western] countries, peoples' diet changed substantially in the second half of the twentieth century, generally with increases in consumption of meat, dairy products, vegetable oils, fruit juice, and alcoholic beverages, and decreases in consumption of starchy staple foods such as bread, potatoes, rice, and maize flour. Other aspects of lifestyle also changed, notably, large reductions in physical activity and large increases in the prevalence of obesity."[18]

    "It was noted in the 1970s that people in many western countries had diets high in animal products, fat, and sugar, and high rates of cancers of the colorectum, breast, prostate, endometrium, and lung; by contrast, individuals in developing countries usually had diets that were based on one or two starchy staple foods, with low intakes of animal products, fat, and sugar, and low rates of these cancers."[18]

    "These observations suggest that the diets [or lifestyle] of different populations might partly determine their rates of cancer, and the basis for this hypothesis was strengthened by results of studies showing that people who migrate from one country to another generally acquire the cancer rates of the new host country, suggesting that environmental [or lifestyle factors] rather than genetic factors are the key determinants of the international variation in cancer rates."[18]

  • by Paul Jakma ( 2677 ) on Wednesday May 16, 2012 @08:45AM (#40015503) Homepage Journal

    I don't know whether it is true whether Chinese eat more calories (I'd be sceptical). From trips to the north of China I've noticed their food is quite different to western food. Chinese there do not eat highly-refined foods as much as we do. Indeed, there is very little sugar in their foods. Their meals have substantial amounts of fresh vegetables, which tend to be cooked more lightly than over here. The most refined things they eat are the dough of their breakfast buns and pancakes, and of their dumpling & won-ton skins! When they snack, they seem to snack mostly on fresh fruit and nuts.

    The calorific content stated for foods here is determined by burning up the food-stuff. I.e. it determines more the /maximal/ energy content. However, our bodies efficiency at digesting food is not uniform. Fibreous and/or more whole foods are literally harder to digest than more refined foods - it literally takes more energy to break such foods down than the more refined foods. Some of that energy goes toward the extra bacteria that are required to pre-process and break-down the extra fibre. Some of that food will literally go undigested, and through us.

    Not all calories are equal.

  • by dunkelfalke ( 91624 ) on Wednesday May 16, 2012 @08:59AM (#40015633)

    Sorry, but this is wrong on so many levels. You see, while you get energy from stored fat, it is a quite energy intensive process itself if fat should be the main energy source. You can experience the "hitting the wall" effect yourself after a long endurance training. When the glycogen storage is depleted, the body switches completely to fat burning and suddenly you don't have any energy to go on and breathe much faster, might even faint.

    Fat burning is meant to be an additional energy source, not the primary one. The reason why fat is stored is:

    1) you have eaten too much food. Otherwise the fat would be all used up

    2) You have got far too much fat mixed with carbohydrates in the food. Well, duh, the body takes what it can use right away and stores what it can use only with some effort.

    Your example with lab rats is very misleading because in the experiment the own control mechanism of rat's organism was artificially overridden. This matters to healthy organisms who don't receive additional insulin exactly how? Right, not at all.

    Oh, by the way, the insulin doesn't just tell "fat cells to open up and absorb it", it also (and this is actually its primary task) tells the muscle tissue and liver to absorb sugar so they can convert it to glycogen, which is the primary source of short- and middle-term energy for your body. Only the absolute excess of carbohydrates is stored as fat - and fat, of course, for already explained reasons.

    Of course, if your glycogen storage is still almost full, then most of what you just ate would be in excess and will be stored as fat. So yes, you indeed get fat because you overeat. Either don't overeat (which is difficult) or deplete your glycogen storage by using your muscles, then you'll be fine.

    The only reason why these "carbs are bad" - posts are marked as insightful is that most people don't want to admit that their own behaviour is a part of the problem.

    Oh, and don't even try to mention Inuit, they are a result of selective breeding and adapting from childhood on. They eat rotten meat that would kill many Europeans due to high levels of cadaverine.

  • by Anonymous Coward on Wednesday May 16, 2012 @09:30AM (#40015931)

    They may be unhealthy to eat for other reasons but when it comes to overweight problems it is calories that count.

    No, it's really carbs that count. Specifically refined carbs (sugar, HFCS, white bread, white rice, etc).

    Seriously, since switching to a high-fat, medium-high-protein, low-carbohydrate diet [] I've been consistently losing 5-10lbs a week even though my calorie count is higher than it was previously.

    I'd highly recommend reading Why We Get Fat [] by Gary Taubes and The Primal Blueprint by Mark Sisson [].

    It really boils down to insulin []. When insulin levels are high, you store fat. When insulin levels are low, you burn fat. Avoiding things that cause insulin responses (simple carbs, artificial sweeteners, etc) results in losing fat. As long as you eat plenty of non starchy vegetables (ie, kale, spinach, collard greens, cauliflower, asparagus, etc) you'll get more than enough nutrition.

  • 1.) My post was refuting the claim that junk food is cheaper than good food. Wegman's is a grocery store that also makes food cafeteria style, and my bloodwork after changing my diet to go to lunch there will attest to the healthiness of the food. I know McDonald's is terrible food. I was saying there's no economic reason to go there.

    2.) The 510 calorie count for a quarter-pounder includes two slices of cheese, which you didn't include in your home-cooked version. There are 70 calories in a slice of cheese. You don't have 146 calories to make up, you have 6. There is no extra crap, there is exactly the correct amount of crap. You don't have to resort to either magic sauce or Hollywood accounting of cheese to make the argument that fast food is awful for you.

  • by Rolgar ( 556636 ) on Wednesday May 16, 2012 @09:54AM (#40016193)

    The things that will make you fat:
    Corn (including HFCS)
    Too much Dairy
    Too many fruits

    Things that won't make you fat are on this shopping list []. 80-90% of what goes in your mouth should be animal proteins and fats and lots of vegetables.

    Look at the list of things that makes people fat and think about fast food.

    Any burger/sandwich place: Fries or chips, Soda pop, and the bun on any burger or sandwich are a recipe for weight gain. Get a salad and the insides of any burger/sandwich, and drink water, and your weight will move toward a healthy equilibrium.
    Fried food: What gets you fat is not the oil that it's fried in, it's the breading on the outside. Get something unbreaded.
    Pizza: All kinds of bad things about the crust.
    Mexican: Tortillas and chips (plus Chipotle's rice) are the killers. Get a taco salad but skip the chips/shell. Have salsa, meat, lettuce, sour cream, cheese, guacamole and enjoy a supper healthy meal.

    Or as you recommend, get some unprocessed meat, add 2-3 vegetables, and you can't go wrong.

    The items on that top list down to and including sugar all act like sugar in the blood stream. Anybody who really wants to learn about weight gain should go look at the website the shopping list is on,

    Mark also recommends moderate exercise totaling about 1 hour a week (1 20 minute cardio, 1 20 minute weight carrying, and a small amount of functional exercises like squats and pushups) to stay fit as opposed to the 30 minutes a day. He does recommend averaging 10,000 steps a day. Although Mark recommends the exercise, he says that weight gain or loss is 80% what you put into your body and 20% activity level.

    Check out the Friday success stories to see how others have benefited from this lifestyle.

  • by Dcnjoe60 ( 682885 ) on Wednesday May 16, 2012 @10:08AM (#40016333)

    I think I found this here like 5 years ago and I've kept it since. []

    I've emailed Richard last year by the way and he's still the weight he achieved in that article 9 years later.

    FWIW: I'm an endomorph who DOES believe that some people hold weight easier, crave carbs and sugar more than others and have a lower BMR. However science is science - these things only make up a small fraction of the work. 95%+ is simply putting in the effort.

    I can also confirm that adjusting diet is far, far far more rewarding than excercise for weight loss, despite other health benefits. Just as his article says.

    I agree with what you post, but research now shows that very often, it's not a craving for carbs, but an actual addiction to them in terms of the way they effect brain chemistry. As such, just like quitting smoking or giving up drugs and alcohol, since there is a chemical dependency, it is not as easy as one would think. Obviously, just as many people can drink and not become alcoholics. Many can overeat and not become addicted to carbs. But for many, they do, and for them, will power often is not enough.

  • by hsthompson69 ( 1674722 ) on Wednesday May 16, 2012 @10:34AM (#40016707)

    To avoid the "appeal to unnamed authorities" fallacy, here's a specific person (Denise Minger) who specifically tore the China Study to pieces, and has graciously put up her formal critique, including references, here: []

    tl;dr - the China Study ignored data that didn't support their basic conceit, and exaggerated data that did.

  • by hsthompson69 ( 1674722 ) on Wednesday May 16, 2012 @10:45AM (#40016887)

    You know what makes you fat? As the article says, input vs. output

    Bullshit. The human body isn't a simple engine - it is a dynamic, actively regulated system. In the case of fat cells, fat accumulation is regulated by the hormone insulin, not by how many calories one puts in one's mouth. When you see that poor bastard that weights 350 pounds, horking down a pizza like he's starving, it's because he *is* -> the carbohydrate in his diet has caused blood sugar spikes, which causes insulin levels to rise, which causes his fat cells to accumulate fat (stealing calories from the bloodstream), leaving his muscles in his body starving. Put another way, in order to protect his body from the toxicity of blood sugar levels, his body is as fat as it *needs* to be.

    To fix obesity, one has to understand the complexity of the human body, and address the true root cause -> carbohydrate intake. Treating it like a simple mathematics equation is the idiot kind of thinking that got us the obesity epidemic in the first place.

  • Diet matters more than exercise, and studies have shown that, in the long term, people who exercise are no more likely to keep off weight. It's controversial because we've been taught otherwise by those trying to sell us exercise equipment and gym memberships.
  • by dunkelfalke ( 91624 ) on Wednesday May 16, 2012 @11:21AM (#40017369)

    Stop spreading that crap already, will you. The human body is complex indeed, but first, your description is wrong and second, in this house we obey the laws of thermodynamics.

    As I already mentioned, sugar goes to muscles and liver first, and only THEN to fat - if there is any unused sugar left so it cannot leave the muscles starving in first place. And even this fat doesn't matter much, it only gets excessive if you eat more than you use. It is a simple mathematics equation and treating carbohydrates as the one and only reason is what killed Atkins.

    And that poor 350-pound-bastard is starving because he lost his feeling for satiation long ago and has replaced it with the the feeling of a stuffed stomach.

Solutions are obvious if one only has the optical power to observe them over the horizon. -- K.A. Arsdall