I’m Not Fat—I’ve Just Got Fat Bacteria

Calorie-in calorie-out takes another hit.

http://www.discover.com/web-exclusiv...-bacteria0505/

By Jocelyn Selim
May 05, 2005 | Biology & Medicine

An expanding waistline may have less to with what a person eats than
what’s already inside, say microbiologists Jeffrey Gordon and Fredrik
Backhed at the Washington University School of Medicine in Saint Louis.
Variations in the population of bacteria living in the gut may explain
why some people pack on extra pounds while others stay slim.



Gordon and Backhed base their claim on a study of two groups of mice,
one exposed to normal intestinal microbes and another raised in a
germ-free bubble. The germ-free mice had 42 percent less body fat, even
though they were fed one-third more calories. When the animals were
inoculated with bacteria from their normal counterparts, the bubble mice
increased their body fat by 57 percent in just two weeks.



“We know that gut microbes have ways of breaking down otherwise
indigestible carbohydrates, increasing the calories available to the
animal, but we thought something else must be at work,” Gordon says. His
team therefore also looked at a hormone that limits fat storage in the
body. They found that the gut bacteria secrete a substance that
interferes with the hormone, causing even more of the calories to be
stored as fat than would happen normally. The result is that
microbe-containing mice pork up, even on a moderate diet.



“Having or not having certain species in our intestinal bacterial
communities may have a profound effect on how efficiently we harvest and
store energy from our food,” Gordon concludes. Killing off the gut
bacteria is not a viable option—it would trigger opportunistic
infections long before it would yield meaningful weight loss—but Gordon
is targeting the fat-promoting hormone itself in hopes of developing a
better diet drug.

"Stacey Bender" wrote in message
...
Calorie-in calorie-out takes another hit.

Do you really think there's a correlation between mice raised in a
"germ-free bubble" and human obesity?

If those mice were eating one-third more calories, but not gaining any
weight, where did it go? Presumably, their bodies were unable to digest the
food, due to the lack of intestinal bacteria. If so, it must have had a
significant effect on their intestinal processes, and they consistency of
their bowel movements. If this were a factor in human obesity, presumably
someone would have noticed the difference it what gets excreted.

The laws of physics have not been repealed...

GG


http://www.discover.com/web-exclusiv...-bacteria0505/

By Jocelyn Selim
May 05, 2005 | Biology & Medicine

An expanding waistline may have less to with what a person eats than
what’s already inside, say microbiologists Jeffrey Gordon and Fredrik
Backhed at the Washington University School of Medicine in Saint Louis.
Variations in the population of bacteria living in the gut may explain
why some people pack on extra pounds while others stay slim.



Gordon and Backhed base their claim on a study of two groups of mice,
one exposed to normal intestinal microbes and another raised in a
germ-free bubble. The germ-free mice had 42 percent less body fat, even
though they were fed one-third more calories. When the animals were
inoculated with bacteria from their normal counterparts, the bubble mice
increased their body fat by 57 percent in just two weeks.



“We know that gut microbes have ways of breaking down otherwise
indigestible carbohydrates, increasing the calories available to the
animal, but we thought something else must be at work,” Gordon says. His
team therefore also looked at a hormone that limits fat storage in the
body. They found that the gut bacteria secrete a substance that
interferes with the hormone, causing even more of the calories to be
stored as fat than would happen normally. The result is that
microbe-containing mice pork up, even on a moderate diet.



“Having or not having certain species in our intestinal bacterial
communities may have a profound effect on how efficiently we harvest and
store energy from our food,” Gordon concludes. Killing off the gut
bacteria is not a viable option—it would trigger opportunistic
infections long before it would yield meaningful weight loss—but Gordon
is targeting the fat-promoting hormone itself in hopes of developing a
better diet drug.

GaryG wrote:
"Stacey Bender" wrote in message
...

Calorie-in calorie-out takes another hit.


Do you really think there's a correlation between mice raised in a
"germ-free bubble" and human obesity?

There's also a fat virus.
http://aolsvc.health.webmd.aol.com/c.../92/101554.htm.

Do you really think we know even 5% of how our hunger and weight
managament systems work yet? In 2004 fmri studies show fat sugar impact
our dopamine system like other drugs. Etc, etc.


If those mice were eating one-third more calories, but not gaining any
weight, where did it go? Presumably, their bodies were unable to digest the
food, due to the lack of intestinal bacteria. If so, it must have had a
significant effect on their intestinal processes, and they consistency of
their bowel movements. If this were a factor in human obesity, presumably
someone would have noticed the difference it what gets excreted.

You think someone would have noticed leptin before 1994 and the
gazillion other hormones and peptides?

Yet they didn't.

"Stacey Bender" wrote in message
...
GaryG wrote:
"Stacey Bender" wrote in message
...

Calorie-in calorie-out takes another hit.


Do you really think there's a correlation between mice raised in a
"germ-free bubble" and human obesity?

There's also a fat virus.
http://aolsvc.health.webmd.aol.com/c.../92/101554.htm.

Do you really think we know even 5% of how our hunger and weight
managament systems work yet? In 2004 fmri studies show fat sugar impact
our dopamine system like other drugs. Etc, etc.


If those mice were eating one-third more calories, but not gaining any
weight, where did it go? Presumably, their bodies were unable to digest
the
food, due to the lack of intestinal bacteria. If so, it must have had a
significant effect on their intestinal processes, and they consistency
of
their bowel movements. If this were a factor in human obesity,
presumably
someone would have noticed the difference it what gets excreted.

You think someone would have noticed leptin before 1994 and the
gazillion other hormones and peptides?

Yet they didn't.

I think you're grasping at straws. As far as I know, every single study in
which obese people were strictly monitored and fed a diet that contained
less calories than they were burning resulted in weight loss.

Leptin *may* have some role in appetite (though the results are very unclear
at this point), but has no role in metabolism.

The laws of physics have not been repealed...much as we would wish them to
be.

GG

GaryG wrote:
I think you're grasping at straws. As far as I know, every single study in
which obese people were strictly monitored and fed a diet that contained
less calories than they were burning resulted in weight loss.

How does that imply the strict equation of calorie in and calorie out?
It doesn't at all. If it did, then why do people who are losing weight
have to eat a lot fewer calories than people who are already at that
weight to maintain the same weight? The body adjust the metabolism down
to maintain the higher weight.

Leptin *may* have some role in appetite (though the results are very unclear
at this point),

I have not read that anywhere. Can you please provide a reference? I am
curious then why the cousins who didn't produce leptin suddenly had
normal hunger levels after getting leptin injections?

The laws of physics have not been repealed...much as we would wish them to
be.

The laws of physics certainly apply, but it's your body system that we
are looking and it's that entire system you have to judge.

Ignoramus22906 wrote:
I am appalled by the possibility of an implication that laws of
physics somehow do not apply to food and body fat.

Specifically, the law of conservation of energy applies to digesting
pies as well as to hydrogen fusion or internal combustion engines.

More spefifically, energy surplus = energy in minus energy out.

Energy surplus, in the context of human body, translates to weight
gain (or loss if the surplus is negative).

Bacteria may modify how many calories eat are actually absorbed
(calories in), fidgeting or higher body temperature may affect how
many calories are going out, but nothing repels the calories in
/calories out equations.

What matters is the end result of how many are spent and consumed. The
simplistic calorie in and out notion completely ignores the system
between the in and out. I am appalled by people who show no interest in
how our body actually works and would rather toss around general
equations rathar than getting dirty in the details.

"Stacey Bender" wrote in message
...
GaryG wrote:
I think you're grasping at straws. As far as I know, every single study
in
which obese people were strictly monitored and fed a diet that contained
less calories than they were burning resulted in weight loss.

How does that imply the strict equation of calorie in and calorie out?
It doesn't at all. If it did, then why do people who are losing weight
have to eat a lot fewer calories than people who are already at that
weight to maintain the same weight? The body adjust the metabolism down
to maintain the higher weight.

I don't believe they do. Our basic metabolism (kcal/lb/day) is not as
flexible as you seem to be implying. If you have links to studies proving
otherwise, please post them.

It takes a certain amount of "work" (expressed in calories or joules) for
use to stay alive and move about each day. If we eat more than this number
of calories, we'll gain weight...if we eat less, we'll lose weight.

People who are losing weight do not have to eat a "lot fewer calories" in
order to lose. You can lose weight with a deficit of only 10 calories per
day...it just takes a long time. FWIW, this is about the same rate at which
people *gain* weight after reaching adulthood - a mere 10 calories per day
of excess calories will result in the typical 1 lb per year that most people
gain. Do that consistently for 10 or 20 years, and you'll "suddenly" find
yourself overweight.


Leptin *may* have some role in appetite (though the results are very
unclear
at this point),

I have not read that anywhere. Can you please provide a reference? I am
curious then why the cousins who didn't produce leptin suddenly had
normal hunger levels after getting leptin injections?

http://www.gpnotebook.co.uk/simplepa...?ID=-100270025

http://dukehealth1.org/obesity/leptin_story.asp

Apparently, leptin was thought to be a "magic bullet" due to some mouse
studies in the early 90's. But subsequent research has not shown it to be
useful in most humans, though experiments are still ongoing (scientists
would love to discover a billion-dollar magic bullet too!).


The laws of physics have not been repealed...much as we would wish them
to
be.

The laws of physics certainly apply, but it's your body system that we
are looking and it's that entire system you have to judge.

I guess I just don't see it as that complex an issue. Clearly some people's
weight is affected by medical issues (e.g., thyroid problems). But many,
many more are affected by their day-to-day food choices, and their lack of
exercise. These have more to do with culture, mental health, one's
relationship to food, and one's priorities in life, than obscure hormones.

--
GG
http://www.WeightWare.com
Your Weight and Health Diary

GaryG wrote:
I don't believe they do. Our basic metabolism (kcal/lb/day) is not as
flexible as you seem to be implying. If you have links to studies proving
otherwise, please post them.

Please show links showing your point.


It takes a certain amount of "work" (expressed in calories or joules) for
use to stay alive and move about each day. If we eat more than this number
of calories, we'll gain weight...if we eat less, we'll lose weight.

And what mechanism decides how those calories are spent? Your body. It
can decide to lower your metabolism a bit to try and keep the weight on.

People who are losing weight do not have to eat a "lot fewer calories" in
order to lose.

I think your position is ideologically based, rather than science based.
Take a look at
http://www.fit-zone.com/library/O/obesity/gain_fat.html where it says:

But the trial's real purpose was to determine how much of a fight the
body puts up when people attempt to change the weight they have
maintained for a long time--why, in other words, dieters tend to bounce
back to where they started. When both lean and obese subjects dropped
weight, "it seemed to set off a bunch of metabolic alarms," Leibel
recalls. The subjects' bodies quickly started burning fewer calories--15
percent fewer, on average, than one would expect given their new weight.
Surprisingly, the converse also seems to be true for weight gain. Even
rotund people have to eat about 15 percent more than one would expect to
stay very far above their set point.

I have a better link but can't find it at the moment.



http://www.gpnotebook.co.uk/simplepa...?ID=-100270025

http://dukehealth1.org/obesity/leptin_story.asp

Apparently, leptin was thought to be a "magic bullet" due to some mouse
studies in the early 90's. But subsequent research has not shown it to be
useful in most humans, though experiments are still ongoing (scientists
would love to discover a billion-dollar magic bullet too!).

I see. It's not being a magic bullet doesn't mean it is not involved in
hunger. It definitely is. It's not the only thing however. There are
multiple overlapping systems. It seems we are probably leptin resistent
in the same way I am insulin resistent. Adding more inslulin doesn't do
me a lot of good, but that doesn't change the role of insulin in the
body. More leptin resistance:
http://www.bellaonline.com/articles/art18240.asp.

Some useful references:
1. http://www.annals.org/cgi/reprint/130/11/938.pdf - Genes and Obesity:
Is There Reason To Change Our Behaviors?
2. http://www.bbc.co.uk/science/horizon...erstrans.shtml -
fatbusters
3. http://www.nature.com/neuro/journal/...ll/nn1452.html - How can
drug addiction help us understand obesity?
4. http://www.nature.com/neuro/journal/...ll/nn1453.html - The
hardship of obesity: a soft-wired hypothalamus
5. http://www.nature.com/neuro/journal/...n0505-551.html -
Neurobiology of obesity
6. http://www.nature.com/neuro/journal/...n0505-552.html -
Obesity on the brain

I guess I just don't see it as that complex an issue.

Our bodies are complex adaptive mechanims. How can't it be complex? Whe
have over a dozen hormones and peptides controlling hunger and weight.
We have two major systems, dopamine and homeostatic, impacting weight.
Where is it simple? Companies are spending billions on a weight loss
pill, they don't have one yet. Does that imply it is simple?

Clearly some people's
weight is affected by medical issues (e.g., thyroid problems). But many,
many more are affected by their day-to-day food choices, and their lack of
exercise. These have more to do with culture, mental health, one's
relationship to food, and one's priorities in life, than obscure hormones.

If you are a black women and you release more ghrelin and that makes you
hungrier, is that obscure?

If you have fewer dopamine receptors and that makes you eat more, is
that obscure?

Your grandma has poor nutrition which makes you get diabetes and pack on
the pounds, is that obscure?

The fact is our weight is controlled almost entirely subconsciously by
many complex systems in the body. When you are hungry it is your body is
making you hungry. Maybe you can resist the feeling of constant hunger
in world of constant tempations, but the vast majority of people can't.

Matthew wrote:
I think the subject line is very telling. Regardless of what
biochemical complexity I choose to blame, I am still fat. Would you
have me leave my body in the hands of pharmacy, waiting around for
them to make a better pill?

Not at all. But i think for the majority of people a pill will be
needed. Hopefully you are one of those people who can do it without the
pill. But keep in mind, if you were one of those people born with out
leptin production you would feel constant intense hunger and you would
be scrounging through the garbage for more food too. For the rest of us
it's just a matter of degree.

Stacey Bender wrote in message
...
GaryG wrote:

I guess I just don't see it as that complex an issue.

Our bodies are complex adaptive mechanims. How can't it be complex?
Whe
have over a dozen hormones and peptides controlling hunger and
weight.
We have two major systems, dopamine and homeostatic, impacting
weight.
Where is it simple? Companies are spending billions on a weight loss
pill, they don't have one yet. Does that imply it is simple?

Clearly some people's
weight is affected by medical issues (e.g., thyroid problems).
But many,
many more are affected by their day-to-day food choices, and their
lack of
exercise. These have more to do with culture, mental health,
one's
relationship to food, and one's priorities in life, than obscure
hormones.

If you are a black women and you release more ghrelin and that makes
you
hungrier, is that obscure?

If you have fewer dopamine receptors and that makes you eat more, is
that obscure?

Your grandma has poor nutrition which makes you get diabetes and
pack on
the pounds, is that obscure?

The fact is our weight is controlled almost entirely subconsciously
by
many complex systems in the body. When you are hungry it is your
body is
making you hungry. Maybe you can resist the feeling of constant
hunger
in world of constant tempations, but the vast majority of people
can't.

I think the subject line is very telling. Regardless of what
biochemical complexity I choose to blame, I am still fat. Would you
have me leave my body in the hands of pharmacy, waiting around for
them to make a better pill?