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MIT Researchers Discover "Metabolic Master Switch" To Control Obesity

New submitter ahbond writes: The meme of the chubby nerd alone in the basement may be a thing of the past. Well, at least the chubby part, if recent work at MIT pans out and we're able to use a biological "master switch" to "dial-in" a persons metabolic rate. “Obesity has traditionally been seen as the result of an imbalance between the amount of food we eat and how much we exercise, but this view ignores the contribution of genetics to each individual’s metabolism,” said senior author Manolis Kellis, a professor of computer science and a member of MIT’s Computer Science and Artificial Intelligence Laboratory and of the Broad Institute.

6 of 381 comments (clear)

  1. I volunteer as tribute. by Anonymous Coward · · Score: 5, Interesting

    Where do I sign up to try?

    1. Re:I volunteer as tribute. by Anonymous Coward · · Score: 5, Interesting

      I follow a proper regimen of computer games and ice cream, and I'm thinner than most people.

      It should be plain to anyone who's met more than a couple of people that people can differ in body shape and muscle mass even with basically the same diet and training.
      I have no idea why some people have become so eager to deny that, but it doesn't seem to stem from a deep seated belief in equality.

    2. Re:I volunteer as tribute. by hey! · · Score: 5, Interesting

      No, they cure it 100% of the time. The problem is few people actually follow a proper regimen.

      Well, we're in dueling half-truths territory here. It's true that altering the balance between your calorie intake and output will inevitably cause your weight to drop. It's also true that this does not work better than a placebo when it comes to sustainable weight loss -- in fact the yoyo effect makes it worse than a placebo. Which leads us to one of only two possible conclusions: either the strategy is faulty or nearly all human beings are faulty.

      One thing I've noticed over the years is how stable weight is when you aren't paying any attention to it. If you weigh yourself regularly at the same time of day, say when you go to do your gym routine, your weight readings will oscillate a percent or so around an average figure; if your average weight is 200 pounds you might get readings mostly in the range 197-203 lbs. This kind of remarkably precise stability doesn't happen by accident. Your nervous system and gut must be working in concert to keep your body composition in equilibrium, and it does an amazingly good job.

      So how far does this feedback mechanism have to be from perfect to be a problem?

      Imagine you're a six foot tall, 25 year old man who weighs 200 lbs. Unless you're a serious athlete that's a bit chunky, but not obese; it puts you at roughly the 75th percentile of American men your age for BMI. Now suppose you gain 1% of your body mass every year. When you are fifty years old you'll weigh 260 pounds. If you have any genetic disposition to obesity-related problems like hypertension, diabetes, or osteoarthritis there's a good chance you'll have one of them, in which case your BMI of 35.3 qualifies you for bariatric surgery according to the NIH guidelines.

      But we don't experience our lives a year at time; the changes you need to stop this have to be done a day at a time. How much of your body weight have you gained on a *daily* basis over the last 25 years? 0.0027%. So when you're 25 and 200 pounds, and your weight measurements are swinging back and forth by three pounds on a daily basis, there's an underlying trend of gaining weight at a literally imperceptible rate of 2.4 grams per day. That about the same as adding a penny to your pocket, and that's only 0.2% of your normal daily weight fluctuation.

      This is the ultimate case of tortoise (underlying bias toward weight gain) vs hare (conscious alteration of calorie balance), and because this race is lifelong the hare is screwed. But slowing the turtle down just a *tiny* bit would alter the race. It'd mean that you wouldn't put on those 60 pounds in the first place, or if you had then an attempt to diet down a few pounds would stick.

      1% a year is good enough for evolution; by the time you're 50 it's supposed to be time for you to make room for your offspring. But most of us would appreciate being able to enjoy another twenty or thirty years of good health.

      --
      Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  2. Expect a LOT more of this stuff... by RyanFenton · · Score: 5, Interesting

    Due to a new technique called "CRISPR-Cas9", there's been a whole lot of rapid development on the gene-identification front, and likely to be an explosion of new ones in coming months/years.

    It's definitely being used here: Linky.

    Likely lots of half/false leads will also come out of all this too, but thanks to all this, we're getting a lot further into exploring the whole nature/nurture beyond simple debating points, and I think it's all amazing and interesting.

    Ryan Fenton

  3. Re:Metabolic rate doesn't vary that much by Anonymous Coward · · Score: 5, Interesting

    To say metabolic rates don't vary significantly is simply wrong. In my own case I eat 3-4000 calories per day with nil exercise. I retain my lean figure despite everything I do to work against that outcome. It is true that just about any obese person could become healthier with less intake of food, but BMR remains an important factor.

  4. Re:Metabolic rate doesn't vary that much by AK+Marc · · Score: 5, Interesting

    Satiety is strongly affected by hormones and genetics - some people can "eat whatever they want" and maintain their weight while some people can't. If you're really strict about observing these people (who often claim they eat 3000+ calories a day and don't exercise), they eat far less than they think they do. I've observed a number of those people, and counted calories on them. It never fails.

    And I've done the same and found the opposite. They actually burn far more calories at rest than BMR would suggest. The basic metabolic rate of people varies largely.

    the obesity epidemic is not caused by differences in BMR.

    Nobody ever said it was. Seems you are ignoring all the science, so you can support your personal opinion about the obesity epidemic. Processed food changes the content of the food. This causes obesity by triggering over-eating in those who aren't eating things required by their body. If you are iron deficient, you'll have cravings. Often for iron-rich food. If your food has the useful contents purged from it, it'll cause over-eating. It's not a "willpower" thing. It's a malnutrition thing. We are eating the bare minimum to not be malnutritioned, and it's making us fat, because the food doesn't have food in it anymore, just flavor. That's what's causing the obesity epidemic.