Discussion on Metabolism

[darkxshade]

I'm sure at one point or another, we all know at least one guy who's just thin/lightweight as hell and (s)he can eat all the high caloric junk food in the world but their weight never goes up, nutrition and body composition(fat%) aside. When we think about the why's or hows, we just naturally assume that this person has a really high metabolism.

But is that really the case?

If the answer is yes, then physiologically, what is it that causes them to burn more calories than your average/typical person when doing nothing? I'm not a scientist but I thought the law of thermodynamics somewhat apply here in regards to conservation of energy where energy cannot be created nor destroyed. So someone of a "higher" metabolism would mean he's spending more energy while at rest than person B of a lower metabolism. So what is it? Does this persons body require more effort to regulate body temperature? Does his stomach process only 50% of the food he eats and the other 50% just goes out the pipe thereby creating a situation such that he's only really consuming"half" his food/calories? What?

It can't be diet or exercise, I know lightweights who barely go out for even a walk but eats more than me yet he maintains his weight and I would gain if I were to stop exercising and I eat fairly healthy.

It can't be body composition since at 175lbs & roughly 12% bodyfat, I have more lean muscle than the other guy who's 145lbs @ 18% bf. So if lean muscle burns more calories than fat then I should have a higher metabolism than him but that does not appear to be the case.

Especially when I was in college, I knew guys who partied all night, drinks, smokes and passes out for 10 hours then spend the next 8 hours sitting in a classroom and another several playing games on their consoles while scarfing down whole pizzas, burgers and weigh 140. Sure they're skinny fat and a physical may show them to be excessively out of shape but that's not the discussion at hand, it's about their ability to maintain weight despite the above. So also exclude the fact that at some point in their lives, it'll catch up to them because when compared to someone who's doing the complete opposite(eating right, exercising, etc) they still gain a pound for taking a week off to rest at 170.

So when faced with the above, you can't help but think that maybe higher metabolism does exist so I'd like to know what their body does that creates this surplus energy expenditure beyond what is normal.

 

[Koing]

http://hcd2.bupa.co.uk/fact_sh...deractive_thyroid.html

Yes it does exisit. I know a guys who can eat a lot and not put much weight on. They have to eat a lot more to put muscle on.

I eat more protein I put muscle on. I eat crap I get fat.

Koing

 

[Hecubus28]

I thought this was posted on here a little while ago but it goes over what you are talking about. Was a pretty good watch.

Text

 

[darkxshade]

Originally posted by: Koing
http://hcd2.bupa.co.uk/fact_sh...deractive_thyroid.html

Yes it does exisit. I know a guys who can eat a lot and not put much weight on. They have to eat a lot more to put muscle on.

I eat more protein I put muscle on. I eat crap I get fat.

Koing

That's a pretty interesting read... so why doesn't overweight people given the supplement to induce hyperthyroidism to assist in faster weight loss? Is there some kind of side effect? It says there's tablet one can take for hypothyroidism which I assume should be able to increase metabolism even for those who doesn't have hypothyroidism?

 

[Kipper]

Body composition/size, cell turnover, differences in heart rate, hormone differences (between men and women, for instance, which govern innumerable amounts of physiologic reactions), protein turnover, medical conditions (e.g. chemotherapy, HIV+, or other hypermetabolic conditions), age, stage of growth (e.g. teens vs. those in middle age), activity, total surface area (of the skin).

It's even been suggested that children who are restless, always moving about, perhaps even "hyperactive" burn more calories than children who don't.

It's not as if the body is somehow violating the laws of energy conservation or thermodynamics, or not absorbing nutrients correctly. The fact remains that due to genetic, environmental, and ultimately, physiological differences, peoples' total ability to expend calories (metabolism) is going to vary wildly. Body composition and activity is only a fraction of the picture.

 

[Kipper]

Originally posted by: Koing
http://hcd2.bupa.co.uk/fact_sh...deractive_thyroid.html

Yes it does exisit. I know a guys who can eat a lot and not put much weight on. They have to eat a lot more to put muscle on.

I eat more protein I put muscle on. I eat crap I get fat.

Koing

Hypothyroidism is a fairly uncommon condition. It was briefly popular as an explanation for obesity about 10-15 years ago but the majority of obese persons do not suffer from it. Thyroid hormone only explains part of the picture.

 

[Deeko]

In college I literally ate mass amounts of fast food 3x and basically weighed what I do now.

 

[M0oG0oGaiPan]

i think a good way to test this would be getting a bunch of guys and getting them to drink lots of beer. Then they would have to run an obstacle course 2 hours later.

 

[Blackjack200]

I think your body can increase it's metabolism substantially by just raising its temperature a half a degree or so. I know when I was fat I was hot all the time, I would go to hockey games wearing a t-shirt. Now that I've lost a lot of weight I think my body has slowed its metabolism and I get cold very easily.

Also, it seems like when I was fat, I fidgeted and moved around a lot more. Now I can watch someone that's talking and not move a muscle for minutes on end.

All this could just be in my head...

 

[coreyb]

It's in your head. I'm skinny as hell and I'm hot constantly. I'm also fidgety.

 

[Koing]

Originally posted by: Kipper

Originally posted by: Koing
http://hcd2.bupa.co.uk/fact_sh...deractive_thyroid.html

Yes it does exisit. I know a guys who can eat a lot and not put much weight on. They have to eat a lot more to put muscle on.

I eat more protein I put muscle on. I eat crap I get fat.

Koing

Hypothyroidism is a fairly uncommon condition. It was briefly popular as an explanation for obesity about 10-15 years ago but the majority of obese persons do not suffer from it. Thyroid hormone only explains part of the picture.

Agreed.

Koing

 

[fleshconsumed]

Originally posted by: coreyb
It's in your head. I'm skinny as hell and I'm hot constantly. I'm also fidgety.

I don't think cold part is in his head. I've lost weight and I've also noticed that I'm much more sensitive to colder temperatures now. Whereas during past winters I wore pretty much nothing at home, now I have to use fleece sweater, and it's still fall. Ever noticed how it's always overweight people wanting to put the thermostat down in the office?

 

[Riverhound777]

I think much of my energy goes to heat. I've always hated the heat. That is why I moved to the coast, and even now when its over 80 i'm dying. Mid 60s is perfect for me. 50s when i'm sleeping so I can use a blanket.

 

[Kipper]

Originally posted by: darkxshade

That's a pretty interesting read... so why doesn't overweight people given the supplement to induce hyperthyroidism to assist in faster weight loss? Is there some kind of side effect? It says there's tablet one can take for hypothyroidism which I assume should be able to increase metabolism even for those who doesn't have hypothyroidism?

I know nothing about the pharmacology but I did find this warning:

Thyroid hormone should not be used to treat obesity in patients with normal thyroid function. Thyroid medication is ineffective for weight reduction in normal thyroid patients and may cause serious or life-threatening toxicity, especially when taken with amphetamines (benzphetamine [Didrex], dextroamphetamine [Dexedrine, in Adderall], methamphetamine [Desoxyn]). Talk to your doctor about the potential risks associated with this medication.

Source: http://www.ncbi.nlm.nih.gov/bo...book=meds&part=a682475

Makes sense, because thyroid hormone essentially speeds up most functions of metabolism (which happens in virtually every cell of the body). Providing additional hormone would essentially simulate hyperthyroidism, associated with massive weight loss, heart conditions, anxiety/paranoia, etc. Hormone treatments in people with normal levels can lead to very, very bad things. For example, a fast-acting insulin injection in a nondiabetic will induce hypoglycemic shock/coma if you don't spike the blood glucose high enough.

 

[KoolDrew]

The naturally lean will generally have good hormonal status. Thyroid levels will be good, have low to normal cortisol, as well as IGF-1, GH, testosterone, etc. All these play an important role. The biggest factor though is that some individuals metabolisms just tend to crank up when faced with overfeeding, so as calories go up so does calorie expenditure as a response. It's not a case of defying the laws of thermodynamics, just both sides of the equation are being effected. Non-Exercise Activity Thermogenesis (NEAT) seems to be high in a lot of the naturally lean as well and is largely responsible for the increase in calorie expenditure, which this study examined...

Humans show considerable interindividual variation in susceptibility to weight gain in response to overeating. The physiological basis of this variation was investigated by measuring changes in energy storage and expenditure in 16 nonobese volunteers who were fed 1000 kilocalories per day in excess of weight-maintenance requirements for 8 weeks. Two-thirds of the increases in total daily energy expenditure was due to increased nonexercise activity thermogenesis (NEAT), which is associated with fidgeting, maintenance of posture, and other physical activities of daily life. Changes in NEAT accounted for the 10-fold differences in fat storage that occurred and directly predicted resistance to fat gain with overfeeding (correlation coefficient = 0.77, probability < 0.001). These results suggest that as humans overeat, activation of NEAT dissipates excess energy to preserve leanness and that failure to activate NEAT may result in ready fat gain.

http://www.ncbi.nlm.nih.gov/pubmed/9880251

The role of NEAT in fat gain has gained a lot of interest recently and I think a lot can be taken from it for individuals attempting to lose weight as well. While little activities don't seem like much by themselves, it's the cumulative effects of all the activities together that make a difference. Why workout hard for 45 minutes out of the day and then sit on your ass for the rest of it? Some can't avoid it because their job requires it, but just getting up and being more active throughout the entire day makes a large difference in total calorie expenditure, and this can be seen from all of the studies done on NEAT.

 

[AyashiKaibutsu]

I have hypothyroidism, and I was fat at one point. I lost most of my fatness before I found out I had it though so I was able to lose weight with a very low metabolism. The thing was my appetite was very low while I wasn't being treated so it was relatively easy for me to diet to the level needed to actually lose the weight. Now that I'm taking medicine for it, I eat more than I was without gaining weight, and indeed one of the side effects of synthroid is increased appetite with unexplained weigtloss.

 

[NAC]

I'm most of the way through the book "Good Calories, Bad Calories".

It's basically 400 pages discussing the questions similar to what you are asking. Scientific and detailed, but some of the chapters are very eye opening. Awesome book if you are interested in this kind of thing.

If I were to summarize parts of the book in a few bullets:
(Please forgive me, I'm no expert and some of the below might be misleading or off the mark):

• Conclusions drawn from a lot of science research on diet & obesity has been very wrong for several decades. This in turn caused government decisions (ie promote reduction of fat as a means to combat obesity & cardiovascular disease), which in turn drove research dollars towards proving that theory, and in turn much of what we're taught about food & obesity is simply wrong.
  
  My favorite chapter had this argument: Almost no-one would dispute that genetics is the main factor in determining height (assuming there is enough nutrition). Genetics drives hormones which determine height. Hence hormones and genetics "tells" the body how long to grow bones and muscle. YET, common theory is that eating tells the body how much fat to put on. Why is it so obvious that genetics "tell" the body how to grow bones and muscle, yet they don't tell the body how to grow fat?
  
  OP, you are quite right that thin people can eat like pigs yet not gain weight. Some people can't. This has been proven in study after study. In addition, studies have shown this to be the case even if each person eats the same diet and the same number of calories.
  
  To take the most complex argument and try to simplify it: The hormone insulin regulates how the body takes sugar from the blood and uses it. When you eat a lot of simple carbohydrates, blood sugar levels spike, causing the body to respond with insulin to reduce the blood sugar levels. It's this insulin response, which is a response to eating a lot of simple carbs, which upsets the body's internal desire for balance. And causes more fat to be deposited. Note that other hormones and genetic factors are still at play and hence different people have different reactions to the same plate of pasta. But generally diet influences hormones which in turn influence how that food is used by the body.
  
  That is why atkins, paloe, south beach and similar diets are so successful. Excess carbohydrates from simple carbohydrates (pasta, rice, potatoes, anything with sugar) are the main culprit.
  
  And it goes further?. put simply - when a person uses energy for people have a higher tendency to store food rather than use it for energy. Those people will therefore have less useable energy and because they have less energy, they'll be less active and be more hungry. A vicious cycle.
  
  Therefore, the book disputes the theory that energy balance is not simply a factor of calories in equals calories "burned" or stored. The book argues that genetics impacts how calories are burned or stored. AND it argues that calories in impacts how calories are burned or stored.

I don't believe the book describes exactly what the body does with excess energy, which was your main question. Or perhaps I skimmed through that section or didn't read it yet. IMO, it is a combination of factors - a person feeling more desire to be active, extra body heat, fidgeting, or simply sending the excess energy out as waste down the toilet.

 

[bobsmith1492]

I've been thin for forever. In college I would eat loads of calories, perhaps 4-5K/day (mmm, chocolate milk!) and never gained any weight.

When I eat more, I have more energy (which leads to burning off what I ate), including fidgityness and a tendancy to go run or cycle. When I eat less, I get cold and don't want to do anything.

It's a simple balance of calories in and energy out. Some people maintain that balance; some people don't.

 

[Kipper]

Originally posted by: NAC
I'm most of the way through the book "Good Calories, Bad Calories".

It's basically 400 pages discussing the questions similar to what you are asking. Scientific and detailed, but some of the chapters are very eye opening. Awesome book if you are interested in this kind of thing.

If I were to summarize parts of the book in a few bullets:
(Please forgive me, I'm no expert and some of the below might be misleading or off the mark):

• Conclusions drawn from a lot of science research on diet & obesity has been very wrong for several decades. This in turn caused government decisions (ie promote reduction of fat as a means to combat obesity & cardiovascular disease), which in turn drove research dollars towards proving that theory, and in turn much of what we're taught about food & obesity is simply wrong.
  
  My favorite chapter had this argument: Almost no-one would dispute that genetics is the main factor in determining height (assuming there is enough nutrition). Genetics drives hormones which determine height. Hence hormones and genetics "tells" the body how long to grow bones and muscle. YET, common theory is that eating tells the body how much fat to put on. Why is it so obvious that genetics "tell" the body how to grow bones and muscle, yet they don't tell the body how to grow fat?
  
  OP, you are quite right that thin people can eat like pigs yet not gain weight. Some people can't. This has been proven in study after study. In addition, studies have shown this to be the case even if each person eats the same diet and the same number of calories.
  
  To take the most complex argument and try to simplify it: The hormone insulin regulates how the body takes sugar from the blood and uses it. When you eat a lot of simple carbohydrates, blood sugar levels spike, causing the body to respond with insulin to reduce the blood sugar levels. It's this insulin response, which is a response to eating a lot of simple carbs, which upsets the body's internal desire for balance. And causes more fat to be deposited. Note that other hormones and genetic factors are still at play and hence different people have different reactions to the same plate of pasta. But generally diet influences hormones which in turn influence how that food is used by the body.
  
  That is why atkins, paloe, south beach and similar diets are so successful. Excess carbohydrates from simple carbohydrates (pasta, rice, potatoes, anything with sugar) are the main culprit.
  
  And it goes further?. put simply - when a person uses energy for people have a higher tendency to store food rather than use it for energy. Those people will therefore have less useable energy and because they have less energy, they'll be less active and be more hungry. A vicious cycle.
  
  Therefore, the book disputes the theory that energy balance is not simply a factor of calories in equals calories "burned" or stored. The book argues that genetics impacts how calories are burned or stored. AND it argues that calories in impacts how calories are burned or stored.

I don't believe the book describes exactly what the body does with excess energy, which was your main question. Or perhaps I skimmed through that section or didn't read it yet. IMO, it is a combination of factors - a person feeling more desire to be active, extra body heat, fidgeting, or simply sending the excess energy out as waste down the toilet.

That is a huge DUH statement. There are a lot of inputs into what determines "expenditure." But ultimately, it DOES boil down to a net caloric deficit to prove weight loss. I would also dispute the premise that certain diets are "more effective" than others. A preponderance of evidence shows that the majority of diets are in fact quite similar with regard to their LONG TERM weight loss, with few exceptions. It does boil down to adherence and a caloric deficit. The problem is that adherence is a very tough issue because it is, after all, very hard to stick to a diet with which you are unfamiliar. All it takes is a single stressful event and you're off the wagon, low carb, Mediterranean, or whatever.

As far as weight loss is concerned, if you can make Atkins work for you, go for it. If a low-fat diet works, go for it. The trick is finding what somebody can stick to, what works for them, and then jiggering from there. If somebody is dead-set against eating vegetables, fine. If they are complying and losing weight, what they are doing is working for them - and that is ultimately the best thing.

A lot of authors focus on insulin, but completely overlook the many hormones that have also been implicated in controlling appetite - gut hormones, fat hormones, and neurotransmitters, to name a few. Pinning weight gain ALL on insulin is a big mistake. Insulin may be responsible for helping to stuff fat cells, but that all begs the question of why there is a need to stuff fat cells in the first place. Simple carbs? Fair enough. But why are people eating the simple carbs, and what determines that?

Do you see how messy this argument is? A "master theory" with a prime mover is a recipe for failure.

 

[NAC]

Originally posted by: Kipper
That is a huge DUH statement. There are a lot of inputs into what determines "expenditure." But ultimately, it DOES boil down to a net caloric deficit to prove weight loss. I would also dispute the premise that certain diets are "more effective" than others. A preponderance of evidence shows that the majority of diets are in fact quite similar with regard to their LONG TERM weight loss, with few exceptions. It does boil down to adherence and a caloric deficit. The problem is that adherence is a very tough issue because it is, after all, very hard to stick to a diet with which you are unfamiliar. All it takes is a single stressful event and you're off the wagon, low carb, Mediterranean, or whatever.

The author would disagree with you. The entire point of the book is it is NOT just a caloric deficit. The book described studies which compared 1200 calorie high carb, low fat diets to unlimited calorie low carb diets. The low carb diets had BETTER results and were easier to stick to.

Originally posted by: Kipper
A lot of authors focus on insulin, but completely overlook the many hormones that have also been implicated in controlling appetite - gut hormones, fat hormones, and neurotransmitters, to name a few. Pinning weight gain ALL on insulin is a big mistake. Insulin may be responsible for helping to stuff fat cells, but that all begs the question of why there is a need to stuff fat cells in the first place. Simple carbs? Fair enough. But why are people eating the simple carbs, and what determines that?

Do you see how messy this argument is? A "master theory" with a prime mover is a recipe for failure.

Here, I agree with you 100%. I was only trying to summarize a 400 page book in a few paragraphs. By definition I was leaving out a lot of detail. The author did not focus only on insulin - far from it. But in my summary I chose to mention it by name because it is a primary one, and is the best known.

 

[Kipper]

Originally posted by: NAC

Originally posted by: Kipper
That is a huge DUH statement. There are a lot of inputs into what determines "expenditure." But ultimately, it DOES boil down to a net caloric deficit to prove weight loss. I would also dispute the premise that certain diets are "more effective" than others. A preponderance of evidence shows that the majority of diets are in fact quite similar with regard to their LONG TERM weight loss, with few exceptions. It does boil down to adherence and a caloric deficit. The problem is that adherence is a very tough issue because it is, after all, very hard to stick to a diet with which you are unfamiliar. All it takes is a single stressful event and you're off the wagon, low carb, Mediterranean, or whatever.

The author would disagree with you. The entire point of the book is it is NOT just a caloric deficit. The book described studies which compared 1200 calorie high carb, low fat diets to unlimited calorie low carb diets. The low carb diets had BETTER results and were easier to stick to.

Uhh, you're simply restating what I said. Overall the issue IS a caloric deficit, but as I said there are inputs into what defines a caloric deficit - i.e. the math is more complicated. Overall, however, it is a simple math equation. As you said in your post above, certain factors influencing storage, etc. influence the overall balance, but these are INPUTS into the ability to "burn" calories. So ultimately, what are we looking at, here? Balance. To suggest that people are somehow gaining weight out of nowhere is ludicrous. The energy has to come from somewhere.

Suffice it to also say that you've reiterated my point that adherence is the most important thing, since adherence to a 1200 kcal diet is notoriously difficult. I've seen 1800 calorie diets prescribed to hospital patients and if they are ambulatory, they end up going to the cafeteria to eat. People on fluid restriction drink from water fountains. OBVIOUSLY the diet which is easier to stick to is going to produce weight loss, but in the long term it's generally found that the type of diet doesn't really matter, only the ease with which it can be implemented.

 

[KoolDrew]

The book described studies which compared 1200 calorie high carb, low fat diets to unlimited calorie low carb diets. The low carb diets had BETTER results and were easier to stick to.

Have you actually looked at these studies? There's a huge difference between "unlimited calories" and just not paying any attention to calories at all. The problem with most low carb studies is either...

1) They completely ignore the fact that a low carb diet will almost ALWAYS result in more total weight loss while in a calorie deficit. However, this is due to water loss, nothing more.
2) Rather than comparing high carb vs low carb they end up comparing one high protein diet to a low protein one, and assume the difference was from the carbs. Based on what we know about protein and it's benefit in fat loss, this is a poor assumption.
3) Other studies simply removed most carbs from a persons diet without monitoring calories. Guess what happens when you remove a large portion of a persons diet? They lose weight.

The studies that have been done with protein and calories staying constant and measuring actual body composition as opposed to total body weight alone show absolutely no difference.

 

[NAC]

Allow me to clarify what I didn't state clearly enough earlier and Kipper highlighted. To describe one (of many) examples in the book. Pg 318 of the paperback:
"a diet of 1850 calories will reduce weight as quickly as a diet of 950 calories"
Where the 1850 calorie diet was in calories - 25% carbs, ~60% fat, 15% protein
And the 950 calorie diet was 50% carbs and an unstated fat/protein balance

I can't debate other comments other than with what I already wrote. And note that I don't claim to be an expert? all I'm doing is describing the one book.