Protein Threshold

A recent review of the 0,25g and 100g protein feed study was sent to me today. It is written by Dr Peter Attia. It is a thorough review on the paper. I do have some points I would like to make based on his review and comments he has made. Overall, my view on the study is that it confirms that protein synthesis can be impacted by large amounts of protein and that this process can occur over a much longer period of time than once thought. It was simply providing evidence that small amounts of protein fed continuously across the day may not be required if the protein source consumed is a food source that contains both fast and slow absorbing protein.

"The protein source in this study was bovine milk, in which most (~80%) protein is in the form of casein (the rest is whey)."

I re-read the study and I misread the milk protein concentrate as whey protein concentrate. So, yes it is a modified milk drink that has casein and whey. I was thinking about this more and I am thinking, who cares? So they used a milk drink and that is not the same as whey. people drink milk, eat food. They do not consume all their calories through whey. Peter says this. For those getting protein mainly from whey, distributing intake over 3-5 meals of at least 20 g of protein each is still necessary for keeping up protein synthesis rates throughout the day and avoiding significant AA oxidation.


For those getting protein mainly from whey, distributing intake over 3-5 meals of at least 20 g of protein each is still necessary for keeping up protein synthesis rates throughout the day and avoiding significant AA oxidation. But with protein sources that are absorbed more slowly, distributing total daily intake across one or two meals likely won’t compromise overall MPS and protein utilization.

Really? Who does that and why?  The idea here is that this paper investigated a food spruce that is likely to be consumed and therefore, in my opinion, starts to replicate real-world scenarios. That is a good thing. yes, it did not use whey and whey is faster absorbing. Cool. Sometimes the science clouds the real takeaways.

Maybe am viewing this too simplistically. My main focus is making it practical and applicable to athletes in the real world. For me, you can consume a shit tonne of protein in whole food form, if you want to and it will benefit you for a comparable long period time based on how big that meal was. Do I recommend doing that, no. Space it out because you will feel fuller throughout the day and it is easier to get the total amount of protein in by doing so.

I read in the study that they used a milk protein concentrate (MPC) that was engineered to have a specific AA profile. See extract from study below. Perhaps I missed what they were referring to as MPC and that it was in fact just cows milk. My understanding was that they created a MPC from cows milk. An MPC

"To circumvent this issue, we produced higher and lower enriched milk protein concentrate (MPC) batches by collecting milk both during and following the cow tracer infusion period, respectively. L-[1-13C]-leucine enrichment was 10.8 and 2.4 MPE in the higher and lower enriched MPC batches, respectively. L-[1-13C]-phenylalanine enrichment was 38.3 and 7.7 MPE in the higher and lower enriched MPC batches, respectively. Accounting for the amino acid profile and enrichment level of both batches, we mixed the higher and lower enriched MPCs in a 67:33 ratio to produce MPC with an L-[1-13C]-phenylalanine enrichment of 31.6 MPE and an L-[1-13C]-leucine enrichment of 8.0 MPE."

​Then there is this statement in the article written by Dr Attia.


"
So, in effect, this study did distribute protein but did so by distributing absorption rather than distributing intake.

I don't see that as the aim of the study. they were not looking at distribution, they were simply looking at what happens over an extended period based on the size of the meal. The next logical step is to have spaced smaller amounts vs single large bolus at 12-hour intervals with matched protein intake. That would be cool to see. 


"This, in turn, means that choice of protein source impacts optimal protein distribution.
For those getting protein mainly from whey, distributing intake over 3-5 meals of at least 20 g of protein each is still necessary for keeping up protein synthesis rates throughout the day and avoiding significant AA oxidation.

So let's be honest here. Who is achieving their protein intake through whey protein alone or as a primary source every day. Hopefully, not many people as that would be;

A: be a terribly bland diet
B) expose the individual to potential for micronutrient deficiencies and
C) Just be bloody awful.


I get it that whey protein can be absorbed faster and yes, that may need more frequent meals based on that specific type of protein yet it is not real-world. The second part of the statement is what really matters.


"But with protein sources that are absorbed more slowly, distributing total daily intake across one or two meals likely won’t compromise overall MPS and protein utilization. Casein is one of the most extreme examples of such “slow proteins,” but generally speaking, solid protein sources will be absorbed more slowly than protein powders and shakes, and because fiber typically impedes absorption, many plant-based proteins are also relatively slowly absorbed (a common exception being pea protein)."

Whole foods are going to be absorbed slower and that for me is really what this study is revealing. If you eat or drink either a single source or a combination of proteins then the result is going to be amino acids floating around your blood stream, being used for MPS and every other cellular function in the body over at least 12 hours if the size of the meal is sufficient. The bigger the meal, the longer the potential duration of this occurring.


I would like to see a comparison of whole milk vs whey vs casein vs chicken vs plant protein with matched protein & AA profile content (if possible). This might clarify some of the science that Attia is talking about whilst also answering the real world question of "Is eating a tonne of protein in a single meal a viable option for some athletes?"

It is interesting and overall, it certainly makes us think about protein and what we need. I still go back to being practical. Great, we know that single meals of 40g or 100g can be effective in driving MPS, yet it is the total amount of protein that is more likely to be the KEY element to seeing positive results over the long term. Therefore, no matter if you are a male, female, young, old, plant-based, omnivore or carnivore - aim to get at least 2-3 g/kg per day into you every day, every week, every year.

Reference
Peter Attia Article
https://peterattiamd.com/protein-anabolic-responses/?utm_source=weekly-newsletter&utm_medium=email&utm_campaign=240128-NL-/proteinanabolicresponses&utm_content=240128-NL-/proteinanabolicresponses-email-nonsubs&utm_source=Peter+Attia&utm_campaign=6a427ce767-EMAIL_CAMPAIGN_2024_01_18_12_06_COPY_01&utm_medium=email&utm_term=0_-d5206691b8-%5BLIST_EMAIL_ID%5D&mc_cid=6a427ce767

Scott Tindal
April 16, 2024
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