Protein Absorbtion

Nutrition
21

[quote]Professor X wrote:
CU AeroStallion wrote:
in the book SLICED which was my introduction into body building and lifting weights (4 years ago) it says on page 61:

“The human digestive system is capable of procssing between 20 and 25 grams of protein from any given meal, so it’s obvious that six meals per day will allow you to digest twice as much protein as three meals”

granted this book was written in 1991 or so, if this was a FACT then it is still a FACT, but who knows?

The rational they are presenting though, is that if you wanna get big, or get lean, you should eat 6 meals a day. I know that Berardi has said that eating 6+ meals a day speeds up metabolism, and he’s also said that it keeps a constant flow of nutrients entering the blood.

So if there exists some hypothetical limit on how much protein you can digest and utilize at one sitting or meal, it would only make sense to eat 6+ meals a day to get the most progress!

Just to point out the obvious…25 multiplied by 6 equals 150. This means that the most protein someone could ever ingest and utilize over 6 meals is only 150gr. If that were true, anyone over 200lbs would HAVE to eat more than 8-10 times a day just to meet the requirements considered by most, especially when dieting. Needless to say, that is ridiculous.

If I weigh 265lbs, I would have to avoid sleep just to make sure I ate enough times to meet my body weight in protein. That quote is bogus info. Proof of this is in any gym with bodybuilders over 250lbs who have ever dieted for a contest without eating 12+ times a day.
[/quote]

I didn’t say that it was correct nor that I held that statement to be true in my mind, I just said it was in the book and presented it as an example of the ‘mythical barrier.’

My take home message was simply that people need to be eating more often than 2 or 3 times per day so there is a more constant flow of nutrients going to replenish the muscle tissue.

You have to wonder what sort of mathematical relationship exists between the amount of protein absorbed and the amount consumed. Obviously if you eat more, you will absorb more, but there has to be a point at which the percentage of protein absorbed over protein consumed starts to drastically decrease. This would eventually lead to a point in which absorption becomes so low that the mythical barrier would become evident.

Even so, such a barrier would probably require a HYUGE amount of protein to be consumed in one sitting. The problem would be that consuming an amount to reach any form of absorption limit would put your body at a point in which you are wasting away a LOT of the protein that you are eating.

So the key here would be for someone to design a study which looks for a specific consumption at which there exists a LARGE percentage of absorbed/consumed protein. The second portion of such a study could also be to find the mythical limit if one indeed exists.

22

Sure, there is a limit. If you surpass it, then you’ll have gluconeogenesis. That limit will depend on your protein needs…

If none of your cells feel a need to grab the amino’s floating by, then they’ll be converted.

Use one of the estimates of protein needs floating around, perhaps 1g/lb of bodyweight, divide it into portions, and chow down.

It doesn’t matter in the slightest what the exact value in grams your body is likely to absorb during any particular meal based on your fatigue and recovery status. Don’t make it so damned complex.

23

[quote]vroom wrote:

There is no evidence that healthy people with functioning kidneys have to worry about protein consumption at any level.

[/quote]

there is also NO research showing no effect of the quantities of protein (The top out of research and kidney function is around 0.9g/lb)that are consumed within the bodybuilding area and kidney function

There is also no decent long term data at any level

There may be negatives at certain levels, there may be positives, but there is no evidence either way. Doesnt mean that something is or isnt happening.

24

[quote]
Watson2K5, the down side of this is, like Seeves said, your body will start to use protein as energy. You want your body to use carb as energy, not protein.
GB[/quote]

Exactly, but my overall concern is not that my body uses protein for energy once in a while if I consume more than needed. My concern is that my friend read that your body can become dependent on protein as it’s main energy source. I’m not sure that I believe this because chemically it’s easier for you body to break down carbs, that’s why I came here.

25

[quote]vroom wrote:
Sure, there is a limit. If you surpass it, then you’ll have gluconeogenesis. That limit will depend on your protein needs…

If none of your cells feel a need to grab the amino’s floating by, then they’ll be converted.

Use one of the estimates of protein needs floating around, perhaps 1g/lb of bodyweight, divide it into portions, and chow down.

It doesn’t matter in the slightest what the exact value in grams your body is likely to absorb during any particular meal based on your fatigue and recovery status. Don’t make it so damned complex.[/quote]

I’m not trying to make anything complicated I truely believe that the more you know the better off you are and the less likely you are to make a mistake. I’ve heard of the one gram per pound, but that can’t be all there is to it. For example I’m fat I’m about 270lbs, but probably 30% or more body fat. My body would need less protein that someone my weight and less body fat because of the lack of muscle. If I’m trying to loose weight I’m taking in low calories and high protein. Obviously I wouldn’t want my body to use protein as energy on a permanant basis because you can’t build muscle this way and you can’t really loose weight either because you’re body is no longer using carbs for energy which are easily stored as fat. These are my concerns. It’s easy to take what someone tells you and just go with it, but it better to research on your own and find out the truth to a topic. This is all I’m trying to do, Be healthy and wise, loose weight, and build muscle. Who couldn’t relate to that?

Thanks for everyone’s input

26

[quote]
Watson2K5, the down side of this is, like Seeves said, your body will start to use protein as energy. You want your body to use carb as energy, not protein.
GB[/quote]

Exactly, but my overall concern is not that my body uses protein for energy once in a while if I consume more than needed. My concern is that my friend read that your body can become dependent on protein as it’s main energy source. I’m not sure that I believe this because chemically it’s easier for you body to break down carbs, that’s why I came here.

27

[quote]Seeves wrote:

I’m not trying to make anything complicated I truely believe that the more you know the better off you are and the less likely you are to make a mistake. I’ve heard of the one gram per pound, but that can’t be all there is to it. For example I’m fat I’m about 270lbs, but probably 30% or more body fat. My body would need less protein that someone my weight and less body fat because of the lack of muscle. If I’m trying to loose weight I’m taking in low calories and high protein. Obviously I wouldn’t want my body to use protein as energy on a permanant basis because you can’t build muscle this way and you can’t really loose weight either because you’re body is no longer using carbs for energy which are easily stored as fat. These are my concerns. It’s easy to take what someone tells you and just go with it, but it better to research on your own and find out the truth to a topic. This is all I’m trying to do, Be healthy and wise, loose weight, and build muscle. Who couldn’t relate to that?

Thanks for everyone’s input

[/quote]

Seeves, if you are trying to lose weight, then most diets on here are low carb. Know why? That’s right. If your carbs are consistantly low, your body will start relying on fat for energy, not carbs or protein.

28

[quote]Seeves wrote:

Watson2K5, the down side of this is, like Seeves said, your body will start to use protein as energy. You want your body to use carb as energy, not protein.
GB

Exactly, but my overall concern is not that my body uses protein for energy once in a while if I consume more than needed. My concern is that my friend read that your body can become dependent on protein as it’s main energy source. I’m not sure that I believe this because chemically it’s easier for you body to break down carbs, that’s why I came here.

[/quote]

If all you eat is protein, your body has no choice but to use protein as energy. If protein is the majority of your intake, with all other nutrients being so low that they barely replace glycogen, it will turn to protein as energy. I don’t see why this would concern you unless you were in ketosis. Your body needs carbohydrates to function with your brain consuming a significant amount. If you don’t provide it, your body will make its own out of what you do feed it. That is what the term “gluconeogenesis” represents.

29

[quote]Professor X wrote:
If all you eat is protein, your body has no choice but to use protein as energy. If protein is the majority of your intake, with all other nutrients being so low that they barely replace glycogen, it will turn to protein as energy. I don’t see why this would concern you unless you were in ketosis. Your body needs carbohydrates to function with your brain consuming a significant amount. If you don’t provide it, your body will make its own out of what you do feed it. That is what the term “gluconeogenesis” represents.[/quote]

Thanks, that’s what I was looking for. Here’s the other part of my question. If you’re body goes into gluconeogenesis will it be trained to use nothing, but protein or if you feed it carbs will it go right back to using the carbs?

Thanks

PS I’m not having any problems currently nor do I plan to in the future I’m just trying to learn as much as I can.

30

[quote]Seeves wrote:
Thanks, that’s what I was looking for. Here’s the other part of my question. If you’re body goes into gluconeogenesis will it be trained to use nothing, but protein or if you feed it carbs will it go right back to using the carbs?

Thanks

PS I’m not having any problems currently nor do I plan to in the future I’m just trying to learn as much as I can.[/quote]

Your body won’t be trained to do anything. Your body is using fats, carbs and proteins all day long as energy in different amounts. Anytime there is a shortage of needed fuel, it will create its own. Provide the fuel that was lacking and it will do fine using it as energy. You say you are trying to learn. The best way to do that is grab a biology book and look up information that has to do with basic digestion. Learn how carbs are used as fuel. Read in detail about gluconeogenesis.

I know I was a nerd when it came to this stuff. I would spend anytime I wasn’t studying for exams in the library and look this stuff up, mostly because I was interested in how the human body worked. It also related directly to bodybuilding. If you learn the basics (and I mean really learn them) you won’t fall for much of the bullshit that is spread out of lack of knowledge. This was why I majored in biology in college. You don’t have to take it quite that far, but you do need to realize the value in learning this stuff for yourself and learning how to research and find this info on your own.

31

Arrgh! This topic will never die!

Vroom is onto the Holy Grail solution there. Calculate daily PRO needs and divide by 6 meals. It’s that simple. If you like, put a little extra PRO in the peri-workout meals.

Does this answer the question of amino acid transport efficiency across enterocytes with escalating single meal intakes?

Nope.

Does it solve the problem of what a one-meal limit should approximate?

Yep.