ExRx.net

Exercise Prescription on the Net
It is currently Fri Apr 18, 2014 3:30 am

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 79 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6  Next
Author Message
 Post subject:
PostPosted: Fri Sep 24, 2010 4:43 pm 
Offline
Deific Wizard of Sagacity
Deific Wizard of Sagacity
User avatar

Joined: Sat Mar 10, 2007 5:44 pm
Posts: 6323
Location: Halifax, NS
I didn't say anitiotics in meat was any more important than any other dietary factor. I just gave it as an example of something than can affect gut health. It's probably up there with bottle feeding in importance. I think over consumption of grains and sugars is a bigger factor.


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 24, 2010 5:44 pm 
Offline
Site Admin
Site Admin
User avatar

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3967
anandsr21 wrote:
Ironman wrote:
Quote:
We are practically carnivores, but not obligate carnivores. We do not convert enough amino-acids to protein to survive just on muscle meat. There are strict limits to how much proteins we can digest safely.

In this section I have quoted again, you are right on the first two, but the 2nd is wrong. There is no evidence to show that anyone with **NORMAL, HEALTHY** kindneys has any limits on protein.

Gluconeogenesis is a very inefficient process so you really don't have to worry about it. Your excess protein is not going to turn into glucose. It just passes through. Try eating an excessively large amount of lean protein at one time and see what happens. You will get gas and maybe even the protein craps. This shows that it just goes through.

You and Nightfall both seem to think that just because you eat something your body is obligated to digest it. That is just plain wrong. If it can it will, if it can't it won't.

Lack of research just means that is something we don't know. You can't just go by hunches. Besides a lot of your hunches must have been made quite some time ago because now we do have the data.


I agree that it will pass through, as it has no other way for it to go. But that is OK only when there are enough calories otherwise. If not then the body will try to get at that energy. That is when it starts to get poisonous. Rabbit Starvation is a fairly well documented phenomenon. It started from NightFall's 70%, 15%, 15%. That would be a dreadful diet on a long term basis. And it seemed by his post that it was his normal diet.

I am not sure about the kidneys capacity, because it would never get tested unless you have only one kidney. The body has a limited capacity to convert protein to glucose. So the ammonia created will be limited. I would think if you have a single kidney then, you would get problems with very high protein diets.

I would think it a waste of money to add the expensive protein in diet just to $h1t it out.


It will try to get at the energy, but it can't. The rabbit tests are utter bollocks. I can't believe you even mentioned them. The one major glaring, obvious problem, is that RABBITS ARE HERBIVORES! People are entirely different and no such thing was found in studies on people.


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 24, 2010 6:11 pm 
Offline
Novice
Novice

Joined: Tue May 04, 2010 5:54 pm
Posts: 85
Its rabbit starvation-- a diet of only low fat meat

http://en.wikipedia.org/wiki/Rabbit_starvation


Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 25, 2010 1:20 pm 
Offline
Site Admin
Site Admin
User avatar

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3967
Travis wrote:
Its rabbit starvation-- a diet of only low fat meat

http://en.wikipedia.org/wiki/Rabbit_starvation


That's right. The problem with that is a rabbit is an herbivore.


Now keep in mind I'm not arguing that you don't need either fat or carbs for energy. I'm also not saying that crapping out protein isn't a waste. I'm just saying it's not bad for people.


Top
 Profile  
 
 Post subject:
PostPosted: Sat Sep 25, 2010 1:45 pm 
Offline
Deific Wizard of Sagacity
Deific Wizard of Sagacity
User avatar

Joined: Sat Mar 10, 2007 5:44 pm
Posts: 6323
Location: Halifax, NS
A cow is a herbivore too but you don't get rabbit starvation from eating cows. The problem with small animals like rabbits and squirrels is that they don't have enough fat on them. A high protein diet with adequate fat is not dangerous, just wasteful as you said.

It sounded like you were criticizing rabbit studies, which are truly bogus, but irrelevant to this discussion.


Top
 Profile  
 
 Post subject:
PostPosted: Sun Sep 26, 2010 12:44 pm 
Offline
Site Admin
Site Admin
User avatar

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3967
stuward wrote:
A cow is a herbivore too but you don't get rabbit starvation from eating cows. The problem with small animals like rabbits and squirrels is that they don't have enough fat on them. A high protein diet with adequate fat is not dangerous, just wasteful as you said.

It sounded like you were criticizing rabbit studies, which are truly bogus, but irrelevant to this discussion.



I was talking about the rabbit being an herbivore because they fed the rabbit meat.


Top
 Profile  
 
 Post subject:
PostPosted: Sun Sep 26, 2010 5:13 pm 
Offline
Novice
Novice
User avatar

Joined: Wed Aug 18, 2010 11:14 pm
Posts: 68
ironman--
I think "rabbit starvation" is when humans eat nothing but very lean rabbit. The wikipedia page discusses it. It sounds like it causes problems when people eat rabbit meat only for a long time and also experience other environmental stress (like trying to survive a very long hard winter out in some cabin somewhere or having been stranded in Northern Canada when your boat can't make it during your attempt to find the Northwest passage or some such.)

I'd heard of this before, but I'm not very familiar with exactly when it's happened or what's required. But it does appear that a diet of 100% rabbit meat isn't functional.


Top
 Profile  
 
 Post subject:
PostPosted: Sun Sep 26, 2010 9:21 pm 
Offline
Site Admin
Site Admin
User avatar

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3967
Oh I see. In that case, I'm getting two completely different things mixed up.

Yea, if you eat nothing but protein, that isn't going to cut it. You can't really get much energy from that. You need fat to go with it. Well if that is what he was talking about that supports what I was saying more than it supports him.

I thought he meant that oddball study where meat damaged the kidneys of rabbits. I was wondering why anyone would bring some quackery like that.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Sep 27, 2010 1:40 pm 
Offline
Novice
Novice

Joined: Mon Sep 22, 2008 8:12 am
Posts: 78
Ironman wrote:
Oh I see. In that case, I'm getting two completely different things mixed up.

Yea, if you eat nothing but protein, that isn't going to cut it. You can't really get much energy from that. You need fat to go with it. Well if that is what he was talking about that supports what I was saying more than it supports him.

I thought he meant that oddball study where meat damaged the kidneys of rabbits. I was wondering why anyone would bring some quackery like that.


Good that it got cleared up while I was sleeping ;-). I think most of the studies are designed with the outcome in mind. Then the researchers, do everything possible to get the expected results, even fudging results. The bright ones will design it so that they don't have to fudge any results. That is a very big problem in science. But that is what the project grant system expects. You need to work on a theory that is already well accepted and add something to it. Going against the stream only makes your hard work get ignored.

The real problem with high protein is that say you eat 300gms of lean protein. Lets say that 100gms are required for body building. The remaining 200gms is going to be converted to glucose. To get 200gms glucose you need to burn 30% of the energy (I am not sure but it seems to me that this energy must come from fat). So you need about 200*4*3/(10*9) = 27gms of fat to go with it, just to be able to use the remaining 200gms of protein. In addition our body requires a lot of fat as a building material. Without this fat you will burn your own fat, and if you don't have enough body fat, you will be in trouble. This kind of leaning out is called Rabbit Starvation.

The other problem is Kleiber's law. Our body has a surface area, with which we discard heat. The metabolic system in our body is very old. It developed even before mammals developed. So all mammals generate heat only proportional to their surface area or approximately relative to their mass. It is a fact that all mammals have an average metabolic rate proportional to their mass to the power of 3/4.

Now for humans our brains are enormous, and they use a whole lot of energy as much as 600calories which would be about 25% of total energy usage of a normal person. That 3 pound organ (<2% of human body) uses up more than 20% of the energy. If you convert 200gms of proteins to glucose you are producing 250kcal of heat during the conversion. This is also part of your metabolic rate.

The effect of the above is that we have a set ideal metabolic rate. There will be a range that is good for us, but the range is not infinitely stretchable. Moderation seems to be an important key.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Sep 27, 2010 2:04 pm 
Offline
Novice
Novice

Joined: Tue May 04, 2010 5:54 pm
Posts: 85
But that 200gm of protein isn't necessarily converted to glucose-- if there are more efficient ways to fuel the body (ie carbs, fat, alcohol) that excess protein will be excreted.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Sep 27, 2010 5:41 pm 
Offline
Advanced Member
Advanced Member

Joined: Sun Jun 24, 2007 3:46 pm
Posts: 1455
anandsr21 wrote:
Without this fat you will burn your own fat, and if you don't have enough body fat, you will be in trouble. This kind of leaning out is called Rabbit Starvation.
Most of the civilized world is dramatically overweight - an almost purely protein diet would probably do them no harm for weeks or months as fat stores deplete.


Top
 Profile  
 
 Post subject:
PostPosted: Mon Sep 27, 2010 7:06 pm 
Offline
Advanced Member
Advanced Member

Joined: Mon Mar 30, 2009 11:04 pm
Posts: 1106
Also just a tip, you wont get rabbit starvation if you eat everything, organs, bone marrow, etc. obviously.


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 29, 2010 5:19 am 
Offline
Site Admin
Site Admin
User avatar

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3967
anandsr21 wrote:
Ironman wrote:
Oh I see. In that case, I'm getting two completely different things mixed up.

Yea, if you eat nothing but protein, that isn't going to cut it. You can't really get much energy from that. You need fat to go with it. Well if that is what he was talking about that supports what I was saying more than it supports him.

I thought he meant that oddball study where meat damaged the kidneys of rabbits. I was wondering why anyone would bring some quackery like that.


Good that it got cleared up while I was sleeping ;-). I think most of the studies are designed with the outcome in mind. Then the researchers, do everything possible to get the expected results, even fudging results. The bright ones will design it so that they don't have to fudge any results. That is a very big problem in science. But that is what the project grant system expects. You need to work on a theory that is already well accepted and add something to it. Going against the stream only makes your hard work get ignored.

The real problem with high protein is that say you eat 300gms of lean protein. Lets say that 100gms are required for body building. The remaining 200gms is going to be converted to glucose. To get 200gms glucose you need to burn 30% of the energy (I am not sure but it seems to me that this energy must come from fat). So you need about 200*4*3/(10*9) = 27gms of fat to go with it, just to be able to use the remaining 200gms of protein. In addition our body requires a lot of fat as a building material. Without this fat you will burn your own fat, and if you don't have enough body fat, you will be in trouble. This kind of leaning out is called Rabbit Starvation.

The other problem is Kleiber's law. Our body has a surface area, with which we discard heat. The metabolic system in our body is very old. It developed even before mammals developed. So all mammals generate heat only proportional to their surface area or approximately relative to their mass. It is a fact that all mammals have an average metabolic rate proportional to their mass to the power of 3/4.

Now for humans our brains are enormous, and they use a whole lot of energy as much as 600calories which would be about 25% of total energy usage of a normal person. That 3 pound organ (<2% of human body) uses up more than 20% of the energy. If you convert 200gms of proteins to glucose you are producing 250kcal of heat during the conversion. This is also part of your metabolic rate.

The effect of the above is that we have a set ideal metabolic rate. There will be a range that is good for us, but the range is not infinitely stretchable. Moderation seems to be an important key.


Now you are contradicting yourself. Which is it? You convert it to glucose or you get rabbit starvation? As for bodybuilding with 100 grams of protein, that isn't going to cut it unless you are a tiny little guy.

As for the rest of that, what does it have to do with what we are talking about?


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 29, 2010 7:19 am 
Offline
Deific Wizard of Sagacity
Deific Wizard of Sagacity
User avatar

Joined: Sat Mar 10, 2007 5:44 pm
Posts: 6323
Location: Halifax, NS
What he said was that if you need to convert protein to glucose but you have insufficient fat resources, you get rabbit starvation. I don't see the contradiction in that.


Top
 Profile  
 
 Post subject:
PostPosted: Thu Sep 30, 2010 3:21 am 
Offline
Site Admin
Site Admin
User avatar

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3967
stuward wrote:
What he said was that if you need to convert protein to glucose but you have insufficient fat resources, you get rabbit starvation. I don't see the contradiction in that.


That's just a side issue, and it depends on the exact cause of rabbit starvation which we are not sure of. The point however was that there is not much conversion to glucose and excess protein is not bad for you.

Then of course there is the point of why did he bring up rabbit starvation when I questioned his silly ideas about gluconeogenesis and claims about excess protein being bad for you. Rabbit starvation is a straw man because I never said that is all you would be eating.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 79 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6  Next


All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: Yahoo [Bot] and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Powered by phpBB® Forum Software © phpBB Group