[celc5]

Fast vs. Slow Protein... Is Casein Bogus?

by Will Brink

Enter stage right, the “fast vs. slow” protein craze. The study that got this craze rolling was called “Slow and fast dietary proteins differently modulate postprandial protein accretion” and was responsible for causing a resurgence of interest in casein. The basic premise of this much-touted study was that the speed of absorption of dietary amino acids (from ingested proteins) varies according to the type of dietary protein a person eats.

The researchers wanted to see if the type of protein eaten would affect postprandial (e.g., after a meal) protein synthesis, breakdown, and deposition. To test the hypothesis, they fed casein (CAS) and whey protein (WP) to a group of healthy adults, a single meal of casein (CAS) or whey WP following an overnight fast (10 h). Using this specific study design, they found:

•WP induced a dramatic but short increase of plasma amino acids.
•CAS induced a prolonged plateau of a moderate increase in amino acids (hyperaminoacidemia)
•Whole body protein breakdown was inhibited by 34% after CAS ingestion but not after WP ingestion.
•Postprandial protein synthesis was stimulated by 68% with the WP meal and to a lesser extent (+31%) with the CAS meal.

The basic non-science summary is: the study found that CAS was good at preventing protein breakdown (proteolysis), but was not so good for increasing protein synthesis. WP had basically the opposite effects: it increased protein synthesis but didn’t prevent protein breakdown. The problem is that they were using fasted subjects for a single meal. ***

Keep that in mind as we move along here…
So far so good right? So what can we conclude from this study and how useful are the results? Like so many studies, the results were interesting—and of little use to people in the real world. Do these results hold up under more “real world” conditions where people are eating every few hours and/or mixing the proteins with other macronutrients (i.e., carbs and fats)?

The answer is probably not, which is exactly what the researchers found when they attempted to mimic a more realistic eating pattern of multiple meals and or the addition of other macronutrients. The follow up study was called “The digestion rate of protein is an independent regulating factor of postprandial protein retention.” Four groups of five to six healthy young men received:

• a single meal of slowly digested casein (CAS).
• a single meal of free amino acids mimicking the composition of casein (AA).
• a single meal of rapidly digested whey proteins (WP).
• repeated meals of whey proteins (RPT-WP) mimicking slow digestion rate of casein (i.e., reflecting how people really eat).

So what did they find? In a nut shell, giving people multiple doses of whey—which more closely mimics how people really eat-—had basically the same effects as a single dose of casein, and mixing either with fats and proteins pretty much nullified any big differences between the two proteins.

*Edit: I'm not saying that I "buy" what this guy is saying regarding whey/casein or his other points. Although, I personally never have spent 1 extra cent on casein. I'm just throwing this out there to get feedback.

[NasD]

celc, I supplement with both proteins and use casein exclusively right before bedtime. That's really where I see the value of casein; I don't have to get up in the middle of the night for a whey protein shake essentially. I want to see what others think as well.

[MuscleGuyinNY]

I believe Casein serves a purpose.

Will be using it before bedtime as well.

[bioman]

Agreed.

[jjohn]

I use UP all the time. I get all I need, and I beleive is essential to eat casein in the morning, as well as at night.

[EctoPower]

Very interesting. I have never purchased casein protein mix, but I eat about 1/2 cup of cottage cheese right before bed. Pretty much the same thing. Other than that, I do not focus on getting any casein throughout the day.

What this guy appears to be saying is that several whey protein meals throughout the day has the same effect over the course of that day as 1 casein meal. That's all well and good during a standard day, but if I want slow digesting protein in my belly while I sleep, it still seems like casein is the way to go. I'm not going to get up several times during the night to slam a WP shake.

[Will Brink]

Originally Posted by celc5

Fast vs. Slow Protein... Is Casein Bogus?

by Will Brink

Enter stage right, the “fast vs. slow” protein craze. The study that got this craze rolling was called “Slow and fast dietary proteins differently modulate postprandial protein accretion” and was responsible for causing a resurgence of interest in casein. The basic premise of this much-touted study was that the speed of absorption of dietary amino acids (from ingested proteins) varies according to the type of dietary protein a person eats.

The researchers wanted to see if the type of protein eaten would affect postprandial (e.g., after a meal) protein synthesis, breakdown, and deposition. To test the hypothesis, they fed casein (CAS) and whey protein (WP) to a group of healthy adults, a single meal of casein (CAS) or whey WP following an overnight fast (10 h). Using this specific study design, they found:

•WP induced a dramatic but short increase of plasma amino acids.
•CAS induced a prolonged plateau of a moderate increase in amino acids (hyperaminoacidemia)
•Whole body protein breakdown was inhibited by 34% after CAS ingestion but not after WP ingestion.
•Postprandial protein synthesis was stimulated by 68% with the WP meal and to a lesser extent (+31%) with the CAS meal.

The basic non-science summary is: the study found that CAS was good at preventing protein breakdown (proteolysis), but was not so good for increasing protein synthesis. WP had basically the opposite effects: it increased protein synthesis but didn’t prevent protein breakdown. The problem is that they were using fasted subjects for a single meal. ***

Keep that in mind as we move along here…
So far so good right? So what can we conclude from this study and how useful are the results? Like so many studies, the results were interesting—and of little use to people in the real world. Do these results hold up under more “real world” conditions where people are eating every few hours and/or mixing the proteins with other macronutrients (i.e., carbs and fats)?

The answer is probably not, which is exactly what the researchers found when they attempted to mimic a more realistic eating pattern of multiple meals and or the addition of other macronutrients. The follow up study was called “The digestion rate of protein is an independent regulating factor of postprandial protein retention.” Four groups of five to six healthy young men received:

• a single meal of slowly digested casein (CAS).
• a single meal of free amino acids mimicking the composition of casein (AA).
• a single meal of rapidly digested whey proteins (WP).
• repeated meals of whey proteins (RPT-WP) mimicking slow digestion rate of casein (i.e., reflecting how people really eat).

So what did they find? In a nut shell, giving people multiple doses of whey—which more closely mimics how people really eat-—had basically the same effects as a single dose of casein, and mixing either with fats and proteins pretty much nullified any big differences between the two proteins.

*Edit: I'm not saying that I "buy" what this guy is saying regarding whey/casein or his other points. Although, I personally never have spent 1 extra cent on casein. I'm just throwing this out there to get feedback.

Of course the above is taken out of context from the article "The Religion of Pre and Post Workout Nutrition" which examines and questions many of the "facts" some hold dear...the full article:

http://www.brinkzone.com/articledeta...d=110&acatid=3

I don't think one should conclude casein is worthless from the above info per se.

[celc5]

Now that I look at your link, you make a good point regarding the context. I can't remember how I stumbled upon your article in the first place. In hindsight, I wish I would have posted a link to clarify. Thanks for chiming in

[CryingEmo]

Micellar Casein FTW.

[maynehood171]

There is a product out there that I use that has 3 differ processed WP along with alpha/beta caseins in it...I also go with the morning, after workout, before bed routine but I do have a question...

Eating anything raises body's insulin...it is said that natural body's GH will not release/remain in the blood if there is insulin present...so wouldn't having casein before bed cause GH to not be released for a long time during the night when we need GH to grow/repair/heal?

[warnerve]

i think all he's saying is don't take casein during the day and expect to be able to change your normal eating patterns. i have always liked will's articles about diet

[maynehood171]

I have just been intrigued enough to wonder about this idea...

[LimitTester]

It definitely seems there are uses for both type of protein. I'm not sure if it is necessary to invest extra in casein protein. If you are drinking milk, you are already getting a lot of casein. I think the breakdown of protein in milk is around 75% casein, 25% whey.

[Schism]

Other studies that I've read have also shown an increase in overall protein synthesis when whey/casein were consumed after a workout, as opposed to just whey or casein alone. I'm sure it's impart due to the quick release of amino's from the whey and the sustained release of the casein over the hours that followed said workout. I personally try to consume a mixture of the two through out the day and then just casein at night. I have noticed better results from this than whey or casein supplementation alone by far. So take from that what you want.........

[bound]

I've gotten to the point where I don't think that protein absorbtion rates make any difference at all. Blood levels of amino acids stay elevated for so long after a solid food meal that I don't really think that I'm ever in need of fast absorbing protein.

I mean really, if I eat a full meal an hour before I work out, then a protein shake while I'm working out, do I really need some fast absorbing whey shake after the workout. I'm sure that I'm still getting aminos from the digestion of the pre-workout meal at that point.

I think a lot of it is just the propaganda from supp companies trying to create a need for a product to sell.

[maynehood171]

Originally Posted by bound

I think a lot of it is just the propaganda from supp companies trying to create a need for a product to sell.

It's always this idea that I'm worried about too. Companies scare tactics to get average americans worried and to buy their products for this or that. Much like the eat protein before bed to help with growth coming from companies that make...protein products, but yet HGH is higher when our bodies aren't trying to digest food (which is stated on a Somastatin inhibitor product I won't mention but again is contradicting methods here)...it ends up being that we have to assess ourselves and see what works best...or the best method

Ps - Anybody else hear awhile back on the news of this woman who died (don't know why or how) but was founded that she had a pantry full of supplements...like over a 1,000 if I remember right that she was taking daily...companies loved her!