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.

Comments

I volunteer as tribute.

[Anonymous Coward]

Where do I sign up to try?

Re:I volunteer as tribute.

[Anonymous Coward]

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.

Re:I volunteer as tribute.

[Evtim]

How come that obesity is a modern day epidemic? Were people in the past ALL starving ALL the time and only barons, priests and kings were obese? I am not sure...looking at the pictures of the villagers where my mom was born [circa 40'ties] I see not a single obese person. Yet, all of them that are alive say they were not starving at all [despite war and shit]. After all they were mostly farmers. But when I ask "what is the major difference between your time and today in terms of food" the answer is unanimous - "sugar". They got 1 small cube of sugar per month, while gorging on fat, protein and grain [man, farmers DO know how to eat]

There is something more here, something hidden [accidentally or deliberately]. Something in our lives today pushes people's bodies in the wrong direction and trying to fix it through genomics seems futile and unwise to me...

I am on no grain, no sugar diet for 14 months already. Of course sometimes I have a piece of cake. In the last 4 weeks not even that. And just now, 5 minutes before finding this tread a colleagues brought chocolate for his newborn. I had 2 small pieces [20 grams in total] and at the moment my heart is racing, I feel dizzy and out of breath, even my hands are shaking a bit. I don't know what the hell is going on here...but I ain't gonna put sugar in my mouth for a long time I can promise you that...

Re:I volunteer as tribute.

[hey!]

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.

Expect a LOT more of this stuff...

[RyanFenton]

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

Re:Metabolic rate doesn't vary that much

[Anonymous Coward]

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.

Cell wear == Engine Wear ?

[rtb61]

Running an engine faster shortens it useful life,hmm, maybe this might not be a good idea. Will turning up the biological clock shorten up the life based around the clock. What is really solved by tweaking your system so that you can eat more junk food, damn, I just imagined the junk food companies incorporating this chemical into the pseudo foods they produce, they would go nuts with it.

Re:Metabolic rate doesn't vary that much

[x0ra]

This thermodynamics argument is oversimplifying things. The human body is not a perfect black box (ie. there is output), and all calories are not biologically processed the same way. Fructose has almost no use in the body whereas glucose is the main fuel, so 2000 calories from glucose will not trigger the same response as 2000 calories from fructose. Moreover, if the body was just consuming this magic "calories" unit, we could all run on electrical power...

Re:Metabolic rate doesn't vary that much

[jonnythan]

I never said "deserve." I was a fat guy, and now I'm not a fat guy. I did it the same way everyone ultimately does it: eating less and moving more. There is some, but not much, person to person variation in BMR. You can calculate your own BMR to a reasonable accuracy using your age, mass, gender, and body composition. From there it becomes an engineering problem: energy in and energy out.

It's a simple problem, but not an easy one. The energy in part is extremely difficult to tackle. Hyperpalatable foods - foods with a combination of fats, salts, and simple carbs or sugars - are a huge problem. They are cheap and make it easy to eat far far more than one needs. It's very difficult to maintain the energy in side of the equation when we spend our days surrounded by calorie-dense, delicious food that is essentially free.

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. The energy equation always wins. You can put someone on an isocaloric diet, measure their mass change over time, and calculate their average calorie expenditure.

Satiety is also strongly affected by the food you eat, which is why low-carb diets are often so effective. It's really rather difficult to eat 3000 calories worth of meat and vegetables a day, while 3000 is no problem when you include bread, chips, ice cream, soda, juice, etc.

On top of that, our society is getting fatter and fatter. It's not because BMR is changing.

tl;dr Variability in BMR from person to person can be explained almost entirely by the known predictors (gender, age, height, fat mass, and fat free mass), and the obesity epidemic is not caused by differences in BMR.

Re:Metabolic rate doesn't vary that much

[AK Marc]

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.

This is precisely what they found.

[tlambert]

The article is vague, but if you changed a person's metabolic rate (how many calories are burnt without exercises) you would also expect them to have a corresponding change in body temperature.

This is precisely what they found.

I've made another posting (later) in which I link to a PDF of the original research paper, if you care to read it.

Re:Metabolic rate doesn't vary that much

[Anonymous Coward]

It's possible his body isn't absorbing all those calories and instead is ejecting them as waste.

Or I suppose he might be a mutant with strange muscle and energy usage.

Or he has some sort of parasite in him.