We’re gonna be looking at the idea that there’s a maximum amount of protein that you can absorb in one meal. It usually, it’s something like 20 to 30 grams of protein. The reason goes that because there’s a limit on the amount of protein you can absorb. It’s a good idea to space your meals out or space your protein out across five or six meals throughout the day because if you were to just lump it all in one or two meals then a big chunk of that protein would be going to waste.
Where did this myth come from?
The true myth is that only 20 to 30 grams of protein can be absorbed. The word absorb is the key error because, in reality, we have virtually an unlimited capacity to absorb amino acids from protein. According to a 2009 paper on Digestion and Absorption, virtually all ingested protein is absorbed by healthy humans. So the terminology is important here and we’re using absorption to simply refer to the passage of nutrients through the gut and then through the intestinal wall and into circulation in the blood and absorption isn’t the issue here you could eat say 300 grams of protein and absorb nearly all of that.
What people really mean, when they ask this question is whether or not protein intakes over say 20 or 30 grams in a single meal is actually used to support muscle building and the literature actually doesn’t have a perfectly clear answer on this question but there is a lot of data out there.
In 2015, Dr. Stu Phillips research group published a review article hinting at the existence of a so-called muscle full effect. The idea that with increasing protein doses you’ll eventually hit a seal Pass which increasing protein further doesn’t do anything extra for muscle protein synthesis. The ceiling has been previously proposed in a pretty large body of literature to be roughly 20 grams. The first study to show this compared 20 grams of whole egg protein with 40 grams of whole egg protein following a leg workout and they found no significant difference between the two groups suggesting that you get all the anabolic bang for your buck that you need with just 20 grams.
Similar results were found in another study where 30 grams of beef protein was just as effective as 90 grams of beef protein. At stimulating muscle protein synthesis and still more research showed that protein consumed beyond 20 grams resulted in increased oxidation, meaning the amino acids were being burned off for energy and increased urea production. Further indicating that there is some sort of limit on the amount of protein that can be used for muscle protein synthesis in one sitting. So far based on this scan of the literature it really seems to be the case that that upper ceiling of how much protein you can utilize in one meal seems to be about 20 to 30 grams.
We think that in practice it isn’t really quite that simple because how much protein you can use in a single meal depends on at least three factors.
- The size of the individual – Seems to be the case that folks with more muscle, tend to need more protein to max out the muscle protein synthesis ponds. So to account for this and general inter-individual variability. The Phillips review suggested 0.4 grams per kilogram or about 0.18 grams per pound as a reasonable upper limit. So for a 120-pound person, it would be about 22 grams but for a 200-pound person, it’d be more like 36 grams. So for bigger guys 22 – 30 grams may actually not be enough protein to fully max out that protein synthetic response.
- The amount of muscle mass being trained – In contrast to the earlier studies, a 2016 paper showed that 40 grams of whey protein was, in fact, better at increasing muscle protein synthesis than 20 grams. Because of many of the earlier studies used lower body training only and this study used a full body training routine this led the authors to believe that when you activate more muscle mass and a workout you require more protein to max out the protein synthetic response.
- The age of the individual – As we get older a well-established phenomenon known as anabolic resistance occurs and this basically means that you need more protein to get the same muscle protein synthesis.
So these factors in mind that the ceiling is no longer looking quite as strict at the twenty or thirty grand marks. I think some individuals especially those who are older who have larger muscle masses and perhaps you do full body training could easily stand to benefit from say 40 or even 50 or perhaps more grams of protein in a single citizen.
This answer still doesn’t seem to satisfy many experts in the field and there seems to be something just wrong with the idea that you ate say 80 grams of protein in a single meal at least half of that would be going to waste when it comes to building muscle and I think a big part of this intuition comes from the idea that most of the research we’ve been looking at so far is based on acute measures of muscle protein synthesis not long term trials in this investigating full-scale muscle hypertrophy. I think a lot of this pushback comes from the intermittent fasting community where it’s common to see folks the huge bonuses of protein say 75 or a hundred grams of protein, so based across one to two meals in a say four to eight hour eating window and I will admit that in the real world this feeding schedule doesn’t really seem to affect their ability to add mass in any way.
One intermittent fasting study from The American Journal Clinical Nutrition found that assuming, on average 101 grams of protein in one four-hour eating window versus a more conventional spread out pattern resulted in no differences in lean mass preservation between the groups.
Another paper found that consuming one meal per day with roughly 86 grams of protein actually showed improvements in body composition when compared to that protein being spaced out more evenly across three meals.
Result
We don’t think we have a perfectly clear answer on how many grams of protein the body can use for building muscle in a single meal? We do know that we have a virtually unlimited capacity to absorb amino acids from protein. How much of that is actually utilized in terms of building new muscle will depend on a whole bunch of factors, not limited to your age the amount of muscle mass that you’re exercising your actual body size and also really importantly the quality of that protein.
IN THIS POST –
Scientific References:
https://www.ncbi.nlm.nih.gov/pubmed/1…
http://www.surgeryjournal.co.uk/artic…
https://www.ncbi.nlm.nih.gov/pmc/arti…
https://www.ncbi.nlm.nih.gov/pubmed/1…
https://www.ncbi.nlm.nih.gov/pubmed/1…
https://www.ncbi.nlm.nih.gov/pubmed/2…
http://ajcn.nutrition.org/content/90/…
https://www.ncbi.nlm.nih.gov/pubmed/1…
Recommended Reading/Helpful Resources:
https://atlargenutrition.com/is-there…
https://www.strongerbyscience.com/ath…
The most amazing resource on muscle protein synthesis ever:
