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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.
Where do I sign up to try?
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
It isn't being ignored; it's part of the equation, and always has been. Metabolic rate acts as a multiplier on the "calories out" part of the equation.
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.
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.
Chaos - everything, everywhere, everywhen
BMR (basal metabolic rate) really doesn't vary much person to person.
Actually, the article is stating precisely the opposite. It states that the BMR is controlled by IRX3 and IRX5, and that this varies from person to person, and thus people have different propensities for fat storage as a result of the state of those genes. They went on to modify the nucleotide in mice, and demonstrated that they had in fact found the regulatory mechanism for the metabolic pathway.
Soooo... Fat people are fat because deserve to be fat... very scientific of you to call a constant something that actually is a variable.
I know many strength trainers, dieticians, and physical therapists that would disagree with you. BMR can vary widely from person to person, whether healthy or sick, and especially between genders. There are tons of medical conditions that will actually mess with BMR as a side effect, as well as definite genetic problems. BMR also changes with age, and various age related conditions. Contrary to the gospel you just tried to spew out, all of these is being researched and tested on a wide variety of populations.
If this research is correct, "what you use" does change if this gene is expressed. So while the x/y equation might not change, both the values of x and y can.
Why is parent modded down? He made a good point, one that most people have seen with their own eyes.
Next door to me lives a sixty-year old man who is rail thin despite living the good life (especially with food) and never exercising. I'm not talking about merely not overweight, this guy is really skinny. His twenty-something daughter is already pretty hefty, not fat yet but will be by the time she's thirty. Same lifestyle, half of the same genes, different results.
That controls the switch they found this year. And so on and so on. The complexity of nature is bested only by the ego of man and his "discoveries".
Sin Pills Rool. ;)
http://www.broadinstitute.org/
You could be right, but would you actually be upset if you were wrong about this?
Part of the issue for people trying to lose weight is that their metabolism slows down to avoid burning calories. The body doesn't like giving up calories that it has already stored, and when it has to do so, it basically figures that times are tough, and it doesn't know when they're going to be good again... so it reduces the metabolic rate, and increases storage of excess calories when they do come in. It's thought that this effect may be permanent, but even if it's not, it is certainly a long lasting one, and it's one of the reasons that, even years after losing a large amount of weight, people have a hard time keeping it off (and most fail). Being able to re-tune ones metabolic rate would help overweight and obese people immensely in not only taking that weight off, but keeping it off in the long run. (Of course, this all ties back into the microbiome in the gut as well. The real takeaway from all the new research into obesity is hardly surprising: The human body is complex, and is extraordinarily good at storing and using energy in efficient ways. Modern diets are only about 10,000 years old, and the calorie rich eating of today is less than 100 years old. And our bodies are still evolved to run during boom and bust cycles, where even the boom cycles are pretty thin compared to the energy uptake/use ratios that the average person has daily.)
Annoyingly enough you are correct. Exercise is a good way of getting fit, but not a particularly effective way of losing weight. I have recently been losing 1 kg a week (for 2 months) mainly because I have had a jaw reconstruction and basically have to eat slowly, and due to some other treatment food doesn't taste that great, so I tend to get bored before I finish a plateful.
Why is parent modded down?
Because it is anecdotal. No matter how true it may be, it is terrible science.
"When life gives you lemons, don't make lemonade. Make life take the lemons back!" -- Cave Johnson
It is better far to follow research at the Broad Institute than to possess a narrow mind.
The diet industry hates him!
The all-calories-are-equal argument does not match biological facts.
Weird, because you clearly don't know when to stop making sounds out of it when you want to control stupidity.
"Old man yells at systemd"
Ugh...usually when people say "metabolic rate" they mean something like BMR - basal metabolic rate. Did you know that we have quite a number of equations which predict BMR from relatively few variables. If what you assert it true - that BMR varies significantly, per person. Then you wouldn't be able to perform a regression on BMR data with any useful correlation.
We do. Hence you are wrong.
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...
the AMA or McDonalds?
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
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. Perhaps there's another explanation for IRX3 and IRX5 and obesity being linked. They mentioned "a complete resistance to a high-fat diet" which sounds like, it adjusts how these mice eat (and certainly doesn't mean the same thing as metabolic rate). Of course, saying you have a miracle obesity cure that means you don't need to change any of your life habits, all based on an experiment with mice, sells better.
Slashdot: providing anti-social weirdos a soapbox, since 1997.
It's no specifically that they eat too much, but rather the fact that fast carbs do not satiate very much, thus their over consumption.
the big problem when you are losing weight is hitting The Wall and landing up violently ill (or so low energy you can't see straight).
Yes, I read the article, and my comment stands. Obesity is, in general, not caused by variance in BMR. Far from it. It's caused by an imbalance between eating and activity habits. There are a lot of factors that go into both the energy in and energy out sides of the equation, from hormone levels to satiety levels to calorie-dense and hyperpalatable foods, etc.
But the bottom line is that obesity in the western world is a factor of overabundance of extremely tasty, calorie-dense food combined with increasingly sedentary lifestyles, causing massive energy imbalance. The person-to-person variation in BMR, which accounts for something like 200 calories 25th-75th percentile, is dwarfed by the energy imbalance caused by dietary habits and lifestyle.
Which just means that people will eat even more, not getting as fat but filling their arteries with cholesterol and other harmful substances. Just like Americans smoke more, and drink more if it is available, they will keep eating to excess.
When people admit the connection between depression and eating fatty foods yielding a drug like high, they may start to fight the American obesity epidemic.
The only thing worse than a Democrat is a Republican.
I understand "resistance to a high fat diet" as resistance of the digestive system to (storing) extra calories from fat, not resistance of the animal to the temptation of eating fat. It's about how they digest, not how they eat.
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.
I suspect the article is some "don't feel so bad for being a fat slob" shit. I suspect it doesn't even claim in the article actually that being fat wouldn't be a result of eating more energy than you burn, but that makes a better blurb so the text has to be there at top of the article.
basically I suspect that the article/prof is just about finding a way to make you feel less hungry if you don't need the energy, so you wouldn't need self restraint to limit you from eating too much.
I refuse to give them clicks.
world was created 5 seconds before this post as it is.
It is nice to consider the genetic factor, but soon we are going to be told genetic expression is modulated by the environment, and especially by what we eat.
This may seems to bring us back to the starting place, but it is not exactly the case, since food quality (and not only quantity) will come into account. At least.
BMR varies wildly. Only those with an above average metabolic rate cling to a universal answer for all.
For me personally, I went from reasonable calorie count and low activity and being 20 lbs below "average" to fewer calories, and the same activity and being 20 lbs above "average". Cutting calories has little effect on my weight. It just makes my body hold calories better. The less I eat, the more efficient I get. BMR is wrong, because it doesn't take into account so many proven effects like that.
Learn to love Alaska
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.
Learn to love Alaska
I suspect it doesn't even claim in the article actually that being fat wouldn't be a result of eating more energy than you burn,
I've never seen anyone argue against that. The points I've seen argued are the liars who assert that the amount burned is fixed and constant between similar people (like BMR calculations).
Learn to love Alaska
That kind of assertion really begs for justification. Is there evidence supporting that basal energy burn doesn't vary much?
Why is parent modded down?
Probably because he's lying about eating 4,000 calories a day and not exercising. Either that or he's on meth, but his post isn't insane enough for that.
"First they came for the slanderers and i said nothing."
The Hacker's Diet hits all the main points.
"First they came for the slanderers and i said nothing."
Original paper, New England Journal of Medicine
http://www.nejm.org/doi/pdf/10...
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.
Not true. A single data point can invalidate a theory. It just can't "prove" anything.
But invalidate, yes.
while (sig==sig) sig=!sig;
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.
This is flat out wrong. The whole point of a regression is to determine the correlation in noisy data. We're not talking about random points here like paint thrown at a piece of graph paper, but rather a correlation between indep. variables vs. dep. variables which have a distribution. That in no way negates the possibility that the mean values of the samples can be tightly correlated to the indep. vars.
Now what might be the physical basis for high variance in basal metabolism vs. low variance? Well, there are about a zillion parameters in the human body with complex interactions, genetic & epigenetic dependencies, etc. that we barely understand! Yet we assume that everyone is the same?
I'll tell you where this unscientific belief comes from--the "soul" model of human consciousness. Most discussions of obesity have a heavy bias toward the view that people simply choose to be pigs. Evidence that this is false is steadily accumulating, as it is clear that simply turning a few knobs on your hormone regulation, or other parameters, could turn you into a completely different person--an obese compulsive eater, a drug addict, etc. Note that it is easier to perturb a well optimized body so as to degrade health and behavioral regulation vs. bringing one from non-optimum to optimum.
No. Not all calories are burned. There is caloric intake, but there is also metabolic efficiency, which can vary with diet, and probably also with individual characteristics.
http://i.huffpost.com/gen/1323...
You have cause and effect reversed. You are going to eat more if you are gaining weight. We understand this relationship correctly when children are growing, when women are pregnant, and when we breed some cattle to be thin and produce milk while others are bred to be heavy so we can harvest more meat off of them.
In evolutionary terms, we eat when we are hungry. We certainly are not the offspring of organisms that failed to observe this simple rule. Those organisms are dead, and if they had any offspring, the offspring are dead too.
And don't forget that people tend to gain or lose weight after poop transplants, tending usually towards the donor's BMI.
There is more, if you care to go do some research. Science is poking holes in the "fat people are lazy and/or stupid" myth almost daily now.
See that "Preview" button?
No, parent is modded down because a bunch of fat hate ppls swarm around all these stories and downvote. Make no mistake, parent isn't modded down- he's downvoted.
Unlike Asia, where no one eats noodles, rice, or rice noodles.
Spend half your money on coke, the other half on drugs to avoid gaining weight, what a life!
Starvation is more fun than ketogenic diets.
Sure, three days without food hurts. It's still better than cutting out all the food I like eating.
The glycemic load of processed carbs is higher than noodles or even rice.
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.
How about some data rather than anecdotes?
I suffer from Chronic Fatigue Syndrome. Basically the mitochondria in my body that are responsible for delivering energy to my muscles and organs don't work properly. There is no known treatment or cure. Before it started I was able to control my weight without too much trouble, but now I'm eating relatively few calories but still unable to lose what I have gained.
Other people with this condition experienced similar problems. They were skinny before, able to eat as they pleased, but once their bodies stopped burning so much energy during normal day-to-day activities they rapidly gained weight. As you say, it's the laws of physics at work. The doctors I spoke to said that this is common and a well established (with studies and data) symptom of CFS.
So, people like myself with CFS are proof that changes in the body can have a vast effect on the base amount of calories burned. This research gives me some hope that a partial fix may one day be found, but I'll probably be an old man before it becomes available. Honestly, if there was an experimental treatment I'd try it, but it doesn't seem to work like that.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Funny, so many developers/coders here, and yet they forget ye old addage 'garbage in, garbage out', or another way, if input > output, guess what happens?
So many people want excuses (it's my genes, it's my metabolism, I'm big boned, blah blah fucking blah). For the VAST majority of people, it's simple, they consume more calories than they burn.... period.
I dropped 30 lbs after keeping a food log for 6 months -- you know what I found, I was initially eating more than I should be, shocker I know! I reduced my calories from ~ 2200 a day to ~1600 and what do you know, I lost about 1-1.5 lb a week every week. It's THAT simple for 99% of the population, why is it everyone claims they're the 1% who have a thyroid or metabolic issue, when they know they're fat cause they fucking eat too much?
People want a pill or quick fix for everything... or an excuse
'The unexamined life is not worth living' - Socrates
> On top of that, our society is getting fatter and fatter. It's not because BMR is changing.
Without a survey of BMRs from 50 years ago and today, or other evidence, that's a bold claim. Many things affect gene expression and perhaps eating some foods (e.g. cabbage, for sake of argument) can cause an expression of genes in an individual that raises BMR. If the consumption of cabbage has fallen then BMRs could have changed. We can't go back in time to check BMRs of 50 years ago, but can test such theories via diet modification today. I don't know what the state or research is, but just wanted to point out that unless you check to see if BMR can change then you can't make the assertion that it has not.
And the glycemic load of IV glucose is even higher. You said "fast carbs". Do these not qualify as "fast"?
The body can only absorb element for which it has enzyme for. http://healthyeating.sfgate.co...
There is also some condition, eg. essential fructosuria (inability to process fructose), which will result element to not be metabolized (and in the previous example, you *will* piss fructose).
Being on meth could make them lose weight?
Even with the same diet and exercise?
So it's not 100% all about diet and exercise then?
Might factors other than meth also possibly contribute, in that case?
For some reason, you are on my "foe" list, though, I can only agree with your comment :-)
Is possible to gain weight by consuming less energy than you expend?
You might be able to eat 12,000 calories and gain 1lb due to contributing factors, but it's breaking the laws of physics to eat only 3,000 calories and gain a 1lb.
You contradicted yourself: ~"They don't over eat, but fast carbs leave you hungry, so you over eat".
It's not about calories, it's about caloric intake > energy expenditure. If you gain more weight eating 2,000kcal of chips than 2,000kcal of turkey, then don't eat 2,000kcal of chips. Eat maybe 1,000kcal of chips or 2,000kcal of turkey. If you are still hungry after eating the chips, but not the turkey, that is contributing factor, but a separate problem that should be addressed.
It's possible to absorb less calories than you eat, but impossible to absorb more.
I don't think there's a direct Einsteinian route from energy to body mass. But there is a direct route from food mass to body mass. Ask any body builder.
No, your children are not the special ones. Nor are your pets.
Your BMR may still be 2000, you just aren't absorbing all 3-4000 calories that you eat. In other words your intestines are crappy and you're pooping out half your calories. :)
Gut bacteria play a huge role in how much nutrition/calories we absorb from our food.
BMR is not the key.
Most people can raise their BMR by exercising to build muscle. But that also increases appetite, so does not solve the problem.
I know several obese people who are strong and very fit, but still fail to lose fat.
IMHO, the nerd stereotype has traditionally been skinny -- someone who lacks the muscular bulk for rough team sports, but whose higher metabolic rate translates into quicker thinking, and possibly attention disorders. The chubby image is a more recent phenomenon, likely related to changes in food culture, such as energy drinks, and everything with HFCS. Of course, being an outlier of any kind is a good starting point for being a nerd, but you only need to look at the population at large to see how the weight distribution has shifted in the past few decades.
Escher was the first MC and Giger invented the HR department.
I am that rail thin person who everybody thinks eats 4000 calories a day.
But everybody is wrong.
I work hard at maintaining my weight.
I count calories, and, yes, when I'm out to dinner with people I can and do eat large quantities of food, but those are large quantities I've made room for in my budget.
Science says that 60 year old good-life-living rail-thin man you're using as your "evidence" is most likely just like me. Unless you've spied on him for years you have absolutely no idea what his complete dietary habits are and your presumption that his weight comes to him easy is insulting.
...with just one weird trick that modifies your DNA.
Chewbacon
The Bible is like Wikipedia: written by a bunch of people and verifiable by questionable sources.
Compare the portion sizes, too. I've been eating mostly Japanese food for the past 10 years, but with western portion sizes (literally eating family sized Japanese portions at each meal). At the same time, my job has become more and more sedentary. Guess what happened? I became the fattest I've ever been in my whole life. I went from 180 lbs to 265 lbs. My wife also gained 50 lbs in the same time frame, even tho it's the food she ate her whole life. Something must have changed our genes, I guess.
In the past year or so, I have reduced my portion sizes and started moving my ass more to keep at around 500 calories below my calculated TDEE. Guess what? My genetics must have changed again because I have lost a bit more than 55 lbs so far. Most of it was from reducing my portions and stopping all soda, now I'm running 3 times a week and trying to build up my endurance to run longer distances. I'm still overweight, but it's going in the good direction. I also feel less hungry and tired than I used to. I do realize that it is not an easy fix and that going back to my previous portion sizes and sedentary life will land me back in the exact same spot. Once I hit my target weight, I'll slowly increase the portion sizes until my weight stabilizes.
yap
That quote was from a computer scientist. If energy in > energy out you will get obese. Genetics isn't going to magically create the fat for you, nor does it magically make exercise take no energy to perform, it just contributes to how big or small the right side of the balance is going to be.
I think part of the problem is even if you say have two people with the same hunger "drive" and they manage to eat the "right balanced diet" for that caloric level there is no guarantee that your desire to eat is going to match your bodies ability to burn that which you eat. So for example, people with this disease might have to live a life where they are always a bit hungry, or walk their asses off every day in order to force themselves to balance out. Anyways, there are many factors that go into obesity, but at some level it is a disease and like someone with asthma or liver failure it means your lifestyle might not be able to be the same as the next guys, or even the way you prefer. I don't like it that I need to workout 4-5 days a week to keep my body weight stable, but that is what I have to do because I have a slow metabolism and prefer exercise over eating very small portions (for me at least normal meal + exercise leaves me less hungry than taking the equivalent calories out of my meals instead, + it has nice side effects like benching 300lbs and a resting heart rate of 52).
Part of the problem is diet and exercise take time. A lot of other medical conditions don't really take that long each day to deal with, you take your pill, carry your inhaler in case you need it etc, but proper diet and exercise means you are probably spending an hour a day making food (or the equivalent hours working to pay for it prepared for you) and another hour or so being active (maybe more if you go to a gym and then need a second shower on workout days) which you might not be lucky enough to get from your work either. It can easily eat up 15 hours a week.
You can already raise your metabolism by taking synthroid. While this might be interesting from a genetic standpoint, there's already a pill that will make you burn more fat.
BMR (basal metabolic rate) really doesn't vary much person to person.
Hold up there skippy:
One study of 150 adults representative of the population in Scotland reported basal metabolic rates from as low as 1027 kcal per day (4301 kJ/day) to as high as 2499 kcal/day (10455 kJ/day);
In what universe does a 243% increase qualify as "doesn't really vary much"?
Making up 'facts' to justify your viewpoint doesn't make them facts, no matter how much you wish it did.
The idea that weight purely depends on intake and activity is as insane as the idea that weight is purely genetic.
Many factors weigh it (no pun intended) and there is no generic "recipe" that applies to all humans.
This MIT thing is not going to be a solution for every obese person, but it may well help some to control their weight better.
Slashdot social media options: AIM, ICQ, Yahoo, Jabber and Mobile Text. Why no MySpace?
Indeed in the past the wealthy were [mostly] obese. Guess what was that thing they could afford but almost no one else could [it was rare and very expensive]
Vegies? Nope.
Fat? Nope.
Protein? Nope.
Sugar? Bingo!!!
Drink half a liter of water. Pound gained, no calories gained.
I know what you mean, just being pedantic. Point being, mass of food does not equate to calories.
That's only a 143% increase - it's 243% of the original value, however.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
Oops. You are correct. I should not post in the mornings before ingesting enough caffeine to raise my basal metabolic rate. :)
Still, that's a huge range of variation to dismiss as "doesn't vary much."
Modern diets are only about 10,000 years old, and the calorie rich eating of today is less than 100 years old.
That's a bit of a fallacy there.
Corn, potato, beans, tomato, turkey, cocoa, peanuts, sunflowers (8-11% of vegetable oil comes from its seeds)... and many more.
All those didn't exist as far as the world is concerned until the discovery of America.
And so many more would only become common and thus cheap after being transplanted to Americas and farmed there on all that empty and rich land, with free slave labor, then traded with the rest of the world.
Sugar was known for thousands of years, but it didn't "take off" until 18th century.
And that's all just before we changed those foods to be better. Wind the clock back mere decades and look up Norman Borlaug.
The bread we eat today could not exist mere 50 years ago.
So, from one side, 10000 years as a limit to the "change in our diet" due to agriculture is nonsense.
From another, we didn't go out there into the wild, experimenting willy-nilly what to grow agriculturally.
We just picked the BEST food for US and planted and cultivated MORE of it.
We have an enzyme which takes a rather rare (in nature) sugar called sucrose and splits it into fructose and glucose so we could both get energy and save energy (eat our cake and have it too) from a single molecule.
We EVOLVED to be able to do that - so we planted crops that make more of that molecule.
Some of us have an enzyme which allows us to digest lactose and get energy from that too - after we wean off from our mom's milk.
So we bred cattle that produce THAT molecule (and fat, and meat, and hides...).
Some Japanese can digest cellulose cause they have special gut bacteria with enzymes which allow them to get energy from algae.
Why all those various ways to harvest energy from all those plants and animals?
Because there never was enough of it. We went hungry.
Again - India mere decades ago. Parts of Africa today. Europe and Americas before that, mere decades not centuries ago.
Heck... centuries ago we had nearly no way to preserve food.
Canning is an early 19th century invention. Refrigeration took decades more. Modern refrigeration took even longer.
Before that we ate when we could, what we could, stored some dried foods and prayed for short winters.
And we went hungry.
We did not "change our diet" 10000 years ago by content, nor did we do it by quantity until recently.
The fact that we ARE getting fat off of modern food PROVES that we have evolved to eat that kind of food.
We did not evolve to not spend those calories by sitting the whole day working, sitting while going from place to place, spending winters in comfortably warm rooms with all that cheap food we don't have to hunt, or plant, or harvest or even steal... right there at our arms reach.
There's no "modern" diet, in a biological sense. Same food, just more of it, more easily.
There IS a modern lifestyle and modern technology. Like cars, electricity, penicillin...
That's the bit we haven't yet figured out how to adapt to ourselves in a way that we get more benefits.
Just like we fixed plants to be more nutritious. Or edible.
There's a technology we figured out long ago that allows us to digest otherwise indigestible or poorly digestible food.
I.e. To get more benefits out of food by adapting it to ourselves.
It's called cooking.
There is a science that's equivalent of cooking for modern life, but it is in its infancy.
It's called ergonomics.
But it is where cooking used to be back when we would scour the ground after a forest fire, looking for animals that got cooked alive.
Mit der Dummheit kämpfen Götter selbst vergebens
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.
Then how do you explain the case of someone with sleep apnea, for example? I used to have obstructive sleep apnea. I would go to the gym 7 days a week and workout for hours lifting weights and doing cardio. I got treated for sleep apnea and not only did I maintain the same pretreatment diet, but worked out less often and lost 50 pounds in a few months. Doctors already know that people who are not getting enough rest have almost no chance of losing weight. So clearly there is more involved than thermodynamics. Almost 10 years after treatment for sleep apnea I have never regained the mass I had prior to treatment.
I know, I know. According to /. all fat people are faggots who are responsible for being fat. That may be true, and maybe all Samoans are evil faggots because they are fat, and Asians are the bestsest people in the world because they are skinny, but isn't being fat a survival characteristic in times when there is a scarcity of food. I mean a nice 6 pack is great in good times, but when times get bad that chiseled fuck is going to starve. During the Renaissance the ideal of physical beauty is what would be considered morbidly obese by the ohh soo knowing and knowegelable scientific guardians of right though at the AMA. Seriously what is wrong with being fat. Some people despite what every right thinking person knows to be true have to work harder at not blowing up than others. Those people would in less forgiving times be outproducing and outspawning those of slighter build.
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.
It's been 20 years since researchers proved, vi a oxygen consumption, that obese people have the same metabolism as normies, with very rare exceptions.
But...it is more lack of activity than overeating. I always lost weight working summers in college. It is the all-day activity that adds 1000 calories or more to your burn rate.
Sedentary burn rate is way under your natural amount to want to eat. You aren't overeating as much as undermoving.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
It doesn't vary much from what can be expected based on known variables: namely, age, gender, fat mass, fat free mass, age. That is, given two people who are otherwise equivalent in terms of age, gender, and body composition, BMR is not going to vary much between them.
In other words, BMR is largely determined by body composition, age, and gender.
Yup. Already seeing them.
I'm overweight. There are reasons for it. The biggest one, though, is simply eating too much. I'm making no excuses, and am not going to call myself beautiful or healthy. I'm not. I know what healthy feels like, and I am not there right now.
Push your fat ass away from the table. People on slashdot should know better.
Here, check this out from one of our own: https://www.fourmilab.ch/hackd...
Now you're contradicting yourself.
You started by saying that it that it doesn't vary between fat people and thin people and only food intake and exercise matters. Now you're trying to argue that the variance is irrelevant because it it is partly caused by differences in fat mass and free fat mass.
Additionally, you're ignoring this line from the link I provided:
The rest of the variation (26.7%) was unexplained. It could not be accounted for by age, gender, fat mass, free mass or any other factor they found.
And this:
In one study, when comparing individuals with the same lean body mass, the top 5% of BMRs are 28-32% higher than the lowest 5% BMR.
I could keep going, but there's no point. You've offered no proof whatsoever to back up the opinions you keep stating as fact and you're contradicting yourself in your own arguments. I'm not going to bother replying any more because this is turning into the equivalent of arguing with a new earther about evolution.
My mom used to tell me her mom would make tomato sandwiches during the war. She loved them and viewed them as a treat. Later she found out that the reason she got them was that was all there was. And my mom was lucky, her parents had some land with some fruit trees and a big garden. I think one of the unfortunate things of today is when you are short of money, it is fast food that is the tomato sandwich, and the tomato sandwich had less calories than a big mac and fries.
I took for granted that people would understand I meant that BMR doesn't vary much between people who are otherwise physically similar. Anyway, from your links, it's only a quarter *of the individual variation.* Did you look up to see what the total between-subject variation was, and therefore how much a quarter of that variation is? Hint: it's not that much. It amounts to about half a candy bar.
As for the second: "However, this study did not account for the sex, height, fasting-state, or body fat percentage of the subjects."
I'm sorry about your illness. That sucks. There are, of course, a number of diseases and disorders that greaty affect the calorie out side of the equation directly. These aren't really very common, however, and cannot even come close to explaining the "obesity epidemic."
My reply to this would be that your eating habits changed without you realize it. This is very, very common, especially if you're spending several more hours a day asleep.
Meth suppresses the appetite. That's why you lose weight on it.
That is half of the equation, it also raises your metabolic rate (your heart rate goes up, you tend to get jittery, you move more).
Have you ever taken an amphetamine? I have, legally for ADHD.
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
Anytime somebody is biased towards their pet it-looks-good-on-paper-and-I-want-it-to-be-true theory, and feels the need to deny actual real word experience, they trot this "anecdotal" rebuttal. In a few cases, it's a valid rebuttal, but it's incredibly overused here.
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
My reply to this would be that your eating habits changed without you realize it. This is very, very common, especially if you're spending several more hours a day asleep.
Except that there is evidence that sleep loss affects your metabolic rate. And while this Mayo Clinic article suggests that sleep deprivation can cause cravings, I can tell you right now that I was on the exact same diet before and after the treatment. But if you bother to Google you can find article after article that quote different studies that suggest that sleep deprivation leads to a slower metabolic rate. So you can go ahead and put your head in the sand and think whatever you want, but doctors and scientists pretty much all disagree with you.
Oh and if you actually knew what sleep apnea was, you'd know that the people sleep, they just don't get rest.
Yes, but homo sapiens did not evolve in an environment with mass availability of processed foods. To a certain degree, we evolved to be opportunistic eaters. Agriculture, chemistry and other technology have changed the environment so rapidly that evolution cannot possibly keep up.
I used to believe the idea of eat less/exercise more but that's only part of the picture. Counting calories to lose weight is a fool's errand. Exceed your energy needs by 100 calories a day and you pack on 10 pounds a year.
I now believe the key is to eat less crap (especially simple carbs) and more natural foods so that your body more naturally regulates appetite.
One thing's for certain. The whole "eat more carbs and less fats" message was total BS. Whether it was spread through ignorance or malice, I'm not sure, but I suspect the latter.
Walking is great exercise if you do it fairly quickly. Walking slowly hardly burns calories at all. I suspect walking makes a significant difference. My weight has varied but my wife grouches at my relative skinniness when we eat fairly similarly similarly, but I walk more and faster, at least when we are not walking together. I suspect hurrying and fidgeting heavily impacts metabolic rate.
On the other hand I totally quit desserts a while back and that made it way easier to lose weight. No soft drinks, no desserts. Food is definitely addictive, though. Reducing sugar was hard. And depressing.
You got me into this! You were the ideologue! I'm only a poor assassin! - Twenty evocations, Bruce Sterling
So let's say in some people there is a very small push by the body to reach a high set point weight, they don't have a large appetite, they don't have a strong desire to eat, they don't have horrific hunger pangs when they try to eat less, they don't absorb as much of the extra calories from food, their body doesn't shut down the energy pipeline the second they've had less than ideal calories. And in another person, the exact opposite is true on all counts to the point where losing weight requires constant, brutal suffering. Will power? Fucking idiots. As though the workings of the human body and it's drives are as simple as "calories in, calories out" way be an idiot.
ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn
I saw a study about six months ago where the basal metabolic rate was surveyed in a small population of about 25 people, and the individual with the lowest BMR would have had to run 10 km a day to equal what the person with the fastest BMR would burn in a day sitting around.
That's cool, actual numbers. I like your comment.
So at 10km, that means the highest will be needing to eat 700 calories more than the lowest, not 2000 calories more than the (high) average. So we can conclude the ggp is probably lying.
"First they came for the slanderers and i said nothing."
Yes, it's quite possible to gain weight while consuming less energy than you expended. In fact, all four of the permutations are possible:
1) Weight decreases while energy input < energy spent: you're dieting and/or exercising and are losing weight as a result.
2) Weight decreases while energy input > energy spent: for various reasons (gut flora being the biggest), different people metabolize foods differently, resulting in differing efficiencies in how well they can metabolize the food they eat. Details below.
3) Weight increases while energy input < energy spent: you consumed something that's heavy but low in calories, such as water.
4) Weight increases while energy input > energy spent: you're eating more than you need and are gaining weight as a result.
Going back to #2, pretend that you and I each consume identical meals and engage in identical activities tomorrow. Because our gut flora are different, we'll break down foods differently. My flora may be better at breaking foods down into energy my body can absorb, whereas yours are not as efficient. That may be good for you, however, since if we eat the same 2500 calories today, you may only get 1500 calories of energy out of it, with the other 1000 calories passing through you, whereas I may get 2000 calories out of those same meals. If we then each engage in 1800 calories' worth of activity during the day, you'll be at a 300 calorie deficit, resulting in fat reserves getting burned, whereas I'll be at a 200 calorie surplus, resulting in an increase in my fat reserves.
All of which is to say, weight can change for all sorts of reasons. At least for me, I've found that getting a good scale and eliminating as many of the sources of variation as possible (i.e. check it in the morning after I've relieved myself, before breakfast, while I'm still wearing the same bed clothes I always wear) makes it easiest to track change over time and trends. By the time I get to work, the season and the meetings I'll be in that day will have affected the weight of the clothes I chose to wear, how much sleep I got will dictate whether I got a cup of coffee immediately or waited for awhile, and how late I woke up will have affected whether I grabbed breakfast or skipped it, all of which change from day to day and all of which would add useless noise to any measurements I'd be doing.
I feel your pain, brother. Truly, I do.
I rest my case.
So clearly there is more involved than thermodynamics.
Not true. But I see where your confusion lies...
It's still energy in vs energy out. What you are assuming is that the "energy in" portion of the equation is a simple matter of just adding up what you eat. And that the "energy out" portion is a simple matter of taking your BMR and adding in how many calories a machine says you burned in whatever exercise you did.
Really what each side of the equation is this:
energy in = [what you eat] - [what your body doesn't actually absorb (which is variable)]
energy out = [BMR (which is also variable)] + [calories burned in exercise (which is again also variable)]
So, for you with your lack of sleep, your body's metabolism dropped and therefore the BMR portion of the equation dropped too leaving you with a surplus of energy in vs your energy out.
I'm sure there were also a ton of other factors in there that moved around the various components of the equation too. But it's still energy in vs energy out.
I'm sure there were also a ton of other factors in there that moved around the various components of the equation too. But it's still energy in vs energy out.
Fine, you're right in a sense, but the point is that the GP was claiming that the BMR does not really change from person to person (other than just due do factors such as age and size) and that it is a far more simple equation than it actually is. That's the point I am trying to make, that it's not a simple equation because there are far more variables than the GP claims. That there are variables that have absolutely nothing to do with exercise or food intake that affect your ability to lose weight. Variables that can cause your body to store energy when it normally would not. The only way to make it as simple as the GP claims is if you are starving yourself to the point where your body has no choice but to feed on itself.
The caloric intake argument is still bs. If you drink a litter of gasoline, or about 8000kcal, putting aside its toxicity, you won't grow fat because of it. Eat 2000kcal worth of lettuce, and you won't be able to extract that much energy out of it as well because your body cannot break down the cellulose. On the opposite side, eat 2000kcal worth of pure glucose in one batch, and your body (especially your pancreas) will completely freak out.
Auto-immune/genetic disorder? There are several which could cause this, e.g. Ehlers-Danlos, Marfan syndrome, etc. They can be of varying degrees of severity so if he does have one of them, he may be at the "lucky" end of the scale (skinny, can't really gain much weight, hypermobile joints).
Just an additional possibility.
Those doctors and scientists aren't disagreeing with what I'm saying. I will totally concede that serious medical conditions such as sleep apnea contribute greatly to metabolic rate differences.
My post was about typical people without medical metabolic disturbances.
Not true. A single data point can invalidate a theory. It just can't "prove" anything.
But invalidate, yes.
This is one those things that makes for a great scientific methodology soundbite, but doesn't really accord with real-world scientific practice.
In the real world, and in actual scientific practice, empirical data is frequently flawed or inaccurate in some way. Data points that appear to disagree with a theory may actually agree with it once measurement errors and other methodological problems are taken into account.
If you only have 9 data points that adhere to a theory, but 1 data point that disagrees -- sure, that's probably a good reason to rethink your hypothesis. If you 999,999,999 data points that adhere to a theory, but 1 data point that disagrees, you're not going to just throw up your hands and say, "Oh well, I guess we've disproved it! Science wins!"
No -- actual scientists in that circumstance will spend days or weeks checking every single possible source of error to figure out whether that data point could be wrong. And, chances are, if a billion data points disagree with it, then there's probably something wrong with the data point -- not with the theory.
Of course, we're not dealing with anything close to that level of certainty here. My point is that there are all sorts of reasons why the posts further up in this thread with the anecdotal data could have bad data. It's a well-known fact that people are TERRIBLE at measuring their calorie input, even if they claim to make "food diaries" or whatever. People who are trying to eat less tend to cheat, or they don't measure their food very exactly, or whatever. When you put people into highly controlled lab situations and feed them controlled diets where calories are accurately measured, many of these supposed "anecdotes" turn out to be just examples of poorly collected, and thus inaccurate, data.
Until proven otherwise or backed up by lab results, I always take any anecdotal data about diet claims with a huge grain of salt. Yes, there are variations between people for BMR, and those who criticize fat people need to realize that. But outside of labs, food measurement to determine calorie intake is often inaccurate, due to measurement errors or false/misleading reports or both. There are also plenty of other inputs into the bodily system (and the whole psychology and culture of eating) which can have an influence and can often cause huge measurement errors for these supposed "anecdotes."
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This is flat out wrong.
Not really. :-)
That in no way negates the possibility that the mean values of the samples can be tightly correlated to the indep. vars.
I'll give you that my statement was a tich strong. However the point that the OP is making is that there is variable OTHER than the regressors we currently use that exhibits exceptionally strong control - equal to or greater than the effect of the known regressors combined - over BMR. Even though those variables explain BMR reasonably well. Broadly speaking this claim could be true in several ways:
The regressors could actually be representing our "X factor" and/or our "X factor" explains the currently unexplained portion of the effect or the calculated correlation is random.
The problem with the first idea is that there really are no candidates which explain say...lean body mass - for example. The problem with the second idea is that lean body mass explains quite a bit of the effect. The problem with the third idea is that this has been replicated quite a bit and is based on some known biochemistry.
Well, there are about a zillion parameters in the human body with complex interactions, genetic & epigenetic dependencies, etc. that we barely understand! Yet we assume that everyone is the same?
I'll tell you where this unscientific belief comes from--
Well first we should explain your unscientific belief that this is in fact what either myself or other doctors are describing. It's not that we believe that people are the same but that people are not significantly different in a number of parameters pertaining to BMR. Just because there are lots of things going on in the human body doesn't mean they all affect BMR significantly. That's where your ideas go wrong.
The other problem with your terribly unscientific religion is that you're not controlling for activity or correcting for the fact that people are kind of bad at determining their caloric intake. Considering this conversation was about me correcting someone who claims they take in 3000-4000 KCals/day and doesn't get fat. You appear to immediately take this as evidence supporting your belief without attempting to correct for the fact that this person really doesn't eat that much, or is under 18 or that they're actually more active. It wouldn't take much error in all those parameters to bring that persons actual intake/weight to conform with predictions made from BMR.
Most discussions of obesity have a heavy bias toward the view that people simply choose to be pigs.
This is actually unrelated to what either the OP was talking about and I think that "most discussions" needs to be qualified.
You are...as seems to be your habit...flat out wrong.
Fat and carbohydrates are both burned at the same time. Just in different ratios - the ratios do shift but not by much more than 20%. As usual you want to maximize the total calories burned more than anything else.
Please stop just making things up.
For losing weight, I agree. But what about those who eat large meals, eat cookies etc all the time, popcorn, whatever is around and spend a lot of time sitting around and never gain weight? As reported by those who LIVE WITH the person?
As I understand it, if you eat 1,000 calorie meals three times a day and snack frequently, you'd have to be exercising almost all the time also to not gain lots of weight. There's no time for them to be fasting half the week to make up for it, or spending half the week working out - the people living in the house with them would sort of notice that I'd think.
I suppose it's possible the 3 slices of loaded pizza, 10 oreo cookies and the like are actually much less calories than we would expect - me measure them very wrong. And it's possible everyone who knows people like this are all lying for some weird reason, but that seems unlikely. What reason would someone have to miss or missreport *not* *gaining* weight?
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