T Nation

Protein Absorption...


#1

I was at a nutrition store buying a few things for this competition that I'm getting ready for. Anyway, I went to pick up a protein bar to tide me over until I could get home to eat a real meal. He stated to me that I shouldn't pay any mind to this particular brand b/c my body wouldn't "absorb the total amount of protein stated on the wrapper".

So this got me thinking, how much of the stated 19g of protein in a rocky road Metabolic Drive bar are actually absorbed into the body?


#2

I have a better question, why wouldn't your body absorb all of the protein in any product?

Never believe a supplement/nutrition store employee.


#3

Maybe he was saying it because it was collagen and a poor source of protein?

Or maybe he was thinking BV means how much is absorbed and thus not all will be absorbed?

You would have to ask the guy specifically why he said it.


#4

B-B-B-B-B-B-Bulllllshit.

It's a myth that only certain amounts of protein can be absorbed in each sitting.


#5

If there was a physical issue with the body absorbing protien, why would it matter about that brand of protein bar? I think he just wanted to look smart infront of the hottie and blew it.


#6

LOL--Thanks--you made my morning!


#7

Well, this is why I asked. B/c like I stated previously, it got me thinking.

Thanks for clearing it up!


#8

Are sure that this issue is cleared up, because if all the protein you eat is 100% free for utilisation, then why bother with he big deal over types of protein (apart from absorbsion rates). I've been led to beleive that the BV of a protein is the sum of the nitrogen uptake versus nitrogen excretion? Therefore some proteins offer more bang for you buck.


#9

Lol ... words to live by!


#10

????? Define "absorbed"? All food you intake, short of fiber, is digested and absorbed in your body. What is actually used correctly and not stored as fat is the million dollar question.


#11

I agree with Ghost that it's a myth your body won't absorb more than 30 grams of protein at one meal. But I also believe most protein bars are garbage. Soy protein concentrate has very poor bioavailability. So no, if the bar contains soy (which they mostly all do), you won't absorb all the protein. And chances are it also contains a lot of other junk to make it not taste like shit. Sometimes a bar is necessary to get you to your next meal, esp. when bulking. But I'd never, ever make them a regular part of my diet. That's just me though.


#12

This is simply not true. People with digestive issues often do NOT absorb their food. And people without digestive issues will still have a harder time digesting certain, notoriously hard to digest foods, like soy for example.


#13

There's not really a limit to the amount of protein your body can absorb in a sitting BUT different kind of protein will be more or less absorbed by the body (this is called "bioavailability" or "biological value" or BV). Egg has a value of 100 on that scale and everything is compared to it.

So BV (biological value) is the amount of protein your body is going to absorb (because absorption is not always an efficient process), whatever the amount of protein is.


#14

I take Digestive Enzymes with my protein, which was recommended by Charles Poliquin.


#15

Technically he was right, and we absorb amino acids, not proteins.

MJ look here : -

you can thank me some other time. ;o)


#16

Perfectly stated, thank you!


#17

I believe the definition of BV is a little misconstrued. BV is a measure of how "good" the amino acid content of a particular protein is.

If a polypeptide of straight alanine's were ingested, it would have very poor BV, not because it can't be absorbed, but because the amount of amino acids from that particular protein incorporated into synthesis of our own proteins is not very good.

example. I consume 100 linked alanines. In my body i need an enzyme that contains only 10 alanines. I digest those 100 alanines, and absorb all 100. I only use 10 alanines to build my protein, the rest is worthless to build my enzyme. therefore it is only 10% in terms of BV.

BV is a measurement of the potential efficiently consumed proteins are incorporated into our own proteins.


#18

Jinxed,

I don't think it is fair to include people with "issues" to disprove the general statement that we basically absorb pretty much everthing we eat... ?

People with "issues" need to realize they are not the norm and they have to make adjustements due to their own particular condition when people talk about normal results.


#19

Well, we absorb di- and tri-peptides, as well as amino acids.

[you started it]


#20

As I pointed out in my next sentence, even people with perfectly healthy digestive systems will still absorb soy protein less efficiently than, say, egg protein. Certain foods are not easily digested, by anyone. You might not notice distress, but that doesn't mean the protein in soy is as bioavailable as the protein in eggs or whey, for example.