Leah
00:00:05 – 00:00:45
Welcome to the ideal nutrition podcast. I’m one of your host, Leah Higl, and I’m here with my co-host, Aidan Muir. Today we’re going to be discussing the age old question how much protein can be absorbed in one single sitting? So this is a topic that is often surrounded by a lot of confusion. And that’s not just with the general public, like that’s where dietitians and nutrition coaches alike. Um so there’s definitely a lot of confusion in this space, and I think that comes from a lot of the specific wording and nuance of the physiology and all of that stuff. Um, like many things in in the nutrition space.
Aidan
00:00:45 – 00:01:24
So in talking about the question of how much protein can the body absorb, I think the first issue is probably terminology. Like people when they say absorbed. They probably mean how much can be used for muscle building, and even that doesn’t really solve the debate to make it super simple, which I’ll come back to. But like in prep for this podcast, I googled how much protein in the body absorb because I’m just like I just want to see what people are saying like I’ve heard people, but like, what’s going to be the most common thing? The first thing that came up in the highlighted text before clicking on any links or anything like that was like the most your body can absorb in one sitting is around 25 grams of protein.
Aidan
00:01:24 – 00:02:08
In this case, one setting refers to the time over the course of 1.5 to 2 hours. So that is an interesting way of thinking about it, because 25 grams, it’s not a tiny amount of protein, but it’s not much either. Um, and we’re going to talk through, like later on about, like why that concept can’t even make sense at all. Like when you think about it hard enough, Which is interesting because we talked about like there’s like there are even dietitians for your degrees, et cetera, who might not fully understand this concept. But I I also just think that’s just it’s not in their area. They’ve never had to actually think about it Super, super, super deeply, because when you do think about there will be some. He thinks that kind of make that fall apart. But these kind of statements
Aidan
00:02:09 – 00:02:52
pretty much always based on measuring the acute spike in muscle protein synthesis after consuming the protein. So the way they typically measure it will be something along the graham along the lines of this person needs 10 grams protein, 20 grams, 30 grams, 40 grams. And they check to see how much muscle protein synthesis rises by and whenever it stops, rising significantly more, which is actually a key word that is deemed the optimal amount of protein. The reason why I say that’s a key words because I don’t like you finished your sports dietitians, of course. Recently, Avenue um, there was one side like, I don’t know if you would have the same thing as me. But there was one section on muscle building without talking about muscle protein synthesis, and they whipped up this slide. There’s like 10 grams, 20 grams, kilograms, 40 grams
Aidan
00:02:52 – 00:03:20
and the muscle protein synthesis response and the 40 gram. The muscle protein synthesis was actually a little bit higher than the 30 gram, but it wasn’t statistically significant. So, like so 30 grams of the most you can have that maximise muscle protein services and, like I’m not exactly going to describe myself as a meathead or like a pro science enthusiasts. But like me, looking at that child is like I take the 40 grams like in that shot. Like I take the one that led to more muscle protein synthesis.
Aidan
00:03:20 – 00:03:44
That’s just an interesting point is kind of based on that, and even those studies are not necessarily super consistent. There was even one study that came out over the last two years, where they did it on people who were elderly, and they did a post workout. I think it was a full body session, which we know can increase the amount of protein required. And 70 grams got better outcomes in a lower amount, which is every 30 or 40 grams.
Aidan
00:03:44 – 00:04:23
So it’s like if you just look at that one study, you would come to the conclusion 70 grams is the most you can absorb quote unquote in a single sitting versus all these other people who are. There’s a lot of people who are saying 20 grams is the most you can absorb. It’s pretty size dependent in terms of larger people with more muscle mass. Typically, this limit in what it takes to maximise muscle protein synthesis in a single sitting gets higher for larger people, and it’s a little bit lower towards the 20 grand mark for smaller people. So, as I was saying, there’s a difference between absorption and use for muscle building. We know pretty factually that pretty much all the protein you eat gets absorbed.
Aidan
00:04:24 – 00:05:21
Protein has multiple functions that’s not just used for building muscle has other things that can even, for example, be converted to glucose in the body so I can get absorbed in use for all these other functions. And something to think about is when somebody is wondering how much protein should they eat to build muscle they don’t really care about. They’re not asking what spikes, muscle protein synthesis the most for a one hour period. What they’re asking is how much muscle is just going to help, Like they’re asking about that. We care about longitudinal outcomes more than muscle protein synthesis. So if one study showed that having, for example, this is a hypothetical thing, it’s not actually what we’re really talking about. Somebody had a study where they had 70 grams of protein per meal
and the other one had 30 grams of protein per meal. And they both showed these things in terms of acute muscle protein synthesis. But the 70 grams lead to more muscle growth over 12 weeks. Which one would you care about?
Leah
00:05:21 – 00:05:23
You probably going to go with the one that’s getting the muscle groups.
Aidan
00:05:23 – 00:05:38
So that’s also something to think about. The acute muscle protein synthesis increase is really just a very important but sign. It’s just a sign of what we’re really trying to measure, so that’s something to consider.
Leah
00:05:39 – 00:05:50
I think it definitely comes down to the wording that we’re using, and I think a lot of people say absorbed when they don’t mean absorb.
Leah
00:05:51 – 00:06:40
So there’s obviously like you said, a very big difference between optimising muscle protein synthesis with your protein intake and absorbing all of your protein. So the amount of protein you absorbed from a meal is not dictated by how much protein is in that meal. It can be affected by other things that could be affected by where you’re getting that protein from in regards to protein digestibility of say, legumes versus steak. That’s something that can affect the absorption. Um, but the amount of protein in a meal does not affect the absorption. One thing. One example I like to think of is people on a carnivore diet who are getting most of their calories from protein. If they were to just eat one meal a day, that was just stake. Would they just not absorb those calories? Just not absorb that protein and waste away, even though they’re eating at maintenance calories.
Aidan
00:06:40 – 00:07:10
Yeah, obviously not to put numbers on that, like if you could only absorb, for example, that thing said 25 grams of protein. If that’s all, you could absorb it. All you were eating was protein, which obviously they’re not. They’re eating found as well, but like pretending they only chose lane. Cuts are made like, and you only have 25 grams of protein per meal or whatever, and they ate twice per day. To make this even worse, you’d only end up with 50 grams of protein that you could absorb, and that would be like 200 calories, because there’s four calories per gram of protein. Obviously, that would make this concept not make sense.
Leah
00:07:10 – 00:07:51
Yeah, it would. It would be the ultimate dieting tool if you didn’t absorb all of the protein from a really high protein meal. So it kind of just becomes a bit silly when you start thinking about it like that. So we’d really need to differentiate between our terminology of optimising muscle protein synthesis and absorbs because obviously they are very different things. Um, and the nail in the coffin for this so we’re going back to kind of muscle building is that a lot of research highlights that having between, like 1.6-2.0 grams of protein, particular body weight per day outperforms lower amounts in regards to specifically thinking about muscle building.
Leah
00:07:51 – 00:08:13
But then, if you think about if you can only absorb 25 grams of protein every two hours, like a lot of people aren’t going to be able to reach that total daily protein intake. They require that the research is great for muscle building. If they’re just having five lots of 25 years throughout the day, like it starts to fall apart.
Aidan
00:08:13 – 00:08:54
How could those numbers coexist like they quite literally, can’t coexist unless you’re having like 10 miles per day. Like to give an example. If somebody was 80 kg and they went for the bottom end of that 1.6-2.0 point two grams per kilogram per day kind of spectrum, they’d have to be aiming for 130 grams of protein. And if they ate four meals that were 25 grams of protein. Since that is the max that could be absorbed in this theoretical kind of world, they would only get 100 grams of protein. There’d be 30 grams short of that target. If they ate five meals, they could get to 125. And that’s still just below the bottom of this range. So it is something to consider and be like, Okay.
Aidan
00:08:55 – 00:09:01
Those numbers can’t co-exist. So even if we’re basing it just on the muscle protein synthesis, the fact that still doesn’t cut things fully
Leah
00:09:01 – 00:09:23
Yeah, obviously, like even if you say you pretty much peak muscle protein synthesis, see your body does peak muscle protein synthesis at 30 grams every 2 to 3 hours. There’s obviously still some kind of muscle building effect beyond that, based on the numbers we have for total daily protein requirements for muscle building.
Aidan
00:09:23 – 00:09:32
Yeah, they just don’t up. And in terms of the nail in the coffin, in terms of like, why doesn’t this make sense? Have you ever seen somebody does intermittent fasting and it’s also jacked?
Aidan
00:09:34 – 00:10:13
I’m going real anecdotal here, but no, but that’s the real anecdotal thing, just being like first, like it’s right in front of us. If we see this happening in terms of you could only absorb 25 grams and people could do intermittent fasting and get jacked at the same time. It doesn’t it seems kind of like it’s like what is going on there, but, like if we want to actually go and like, look at the research and do what we should do. Like the research is showing pretty clearly that in these intermittent fasting studies, people are not dropping muscle like crazy, like if calories and protein and matches in some person does like two meals per day in a small leading window and the other person spreads out across the day.
Aidan
00:10:13 – 00:10:31
The calories and protein match the outcomes come out very similarly, particularly calorie deficit. They’re not dropping muscle like crazy, because if you went too deep down this rabbit hole and you’re like, 25 grams of protein or whatever five meals per day or whatever is what it takes to reach this, you’d think that would have drastically superior outcomes, which it doesn’t seem to.
Leah
00:10:32 – 00:10:37
Yeah, so we know. Based on the research that reaching your that kind of 1.6-2.2 grams per kilogram of bodyweight per day is far superior to just having, like that 0.4 to 0.6 grams every three hours and not reaching that total damage. Like we have stats on that.
Aidan
00:10:56 – 00:11:06
Yeah, I love that wording, which kind of leads into the next topic, is kind of like it’s a total protein intake far outweighs timing. Yes, the timing still matters.
Aidan
00:11:07 – 00:11:46
Yeah, if you go once again in fitness, people can go too far to either extreme where they’re like protein. Timing is all that matters. Or people could be like total protein is all that matters can be both. It’s just the way I personally view it is. I say that total protein intake is doing about 90% of what you can to build muscle. That’s not a research based number. That’s just my best inter protection of the research, about 90% and the last 10% comes from things like timing in terms of how it spread out across the day. So in a perfect world, the way to do it is to get that 1.6 to 2.2 point two grand circular, round body weight protein per day. Keeping in mind that the scan complex. But keeping in mind that, like if you’re quite lean, you might want to go towards the higher end of that target or even higher.
Aidan
00:11:47 – 00:12:17
If you have a lot of body fat, your range would actually be a little bit lower. Maybe it’s like 1.4 to 1.8 or something like that. This is just a generalisation in terms of people who lift weights in a kind of let’s start off with. But like we know, total protein intake, whatever that means for you personally is a priority. But then spreading it across the day is still useful because those numbers aren’t made up like those limits in terms of maximising muscle protein synthesis are still important because theoretically, like you maximise muscle protein synthesis.
Aidan
00:12:17 – 00:12:50
You have a gap. You maximise it again. You have a gap. You maximise it again versus the alternative theoretical way of thinking about where it’s like you maximise muscle protein synthesis and then you don’t need again for ages and you’re in a quote unquote catabolic state a long period time. Obviously that’s not the be all and end all otherwise intermittent fasting. People lose muscle like crazy but and still does matter. There is one major study on this to kind of really summarise this from Alan Aragon. And Sean felt really sure if you said it’s going Schoenfeld I never know.
Aidan
00:12:51 – 00:13:21
So I read all this stuff, but like, I don’t know, like reading insane is very different anyway. So from 2013 and the title of this paper is, how much protein can the body absorb in a single sitting for muscle building? And their conclusion, which is the conclusion that I have also come to is that you want to aim for a minimum of and this is the optimal keep in mind. This is optimal for occasion Occasions each day we aim for 0.4 to 0.55 grams per kilogram of body weight, protein per meal, and it’s 4 to 6.
Aidan
00:13:22 – 00:13:41
They can’t say they say a minimum of four I’ll go through. Why? Sixes? Upper limit. Three meals is almost as good as four, so long as you’re still hitting that total protein amount. It’s barely meaningful. Which is why I really emphasised optimal. Because sometimes if I’m working with somebody and three fit success schedule so much better than four.
Leah
00:13:41 – 00:13:47
Yeah, if they’re just going to skip that fourth meal and not hit their daily proof, take that. It makes sense.
Aidan
00:13:47 – 00:14:29
Just put in three. Yeah, exactly. It’s close enough that it doesn’t matter. Um, so that was what was considered to be optimal. And this review included both muscle protein synthesis style data, but also longitudinal outcomes. If you look into it really deeply, you’ll see that there’s not actually that many longitudinal like long term like 12 week studies and stuff like that that will utilise in this particular review. But at the time, that was the best that was available. It’s the best consensus has held up to the test of time since then, like every review on the topic that’s come out since then is kind of aligned with this kind of thinking as well. Why if we look at from that lens where frequent meals or frequent protein feedings is beneficial?
Aidan
00:14:30 – 00:14:37
Still, would there be any doubt started going higher? Like if a body was trying to absolutely optimise their protein intake, Why wouldn’t they have 10 miles per day?
Leah
00:14:37 – 00:14:41
I mean, you can you can, you can Is it feasible?
Aidan
00:14:41 – 00:15:04
I think that’s a big one. Is it feasible? And like it seems like the conclusion is really 4 to 6 meals because it’s like, well, that optimises why would you go above that if you couldn’t? Um, sorry if you didn’t need to. But the other way of thinking about it is do you know about losing threshold? Oh, yeah. You obviously, like you talk about that from vegan perspective. How hard is that to reach that threshold anyway? Particularly a vegan diet on a vegan diet. Very difficult.
Aidan
00:15:07 – 00:15:14
So I imagine you were aiming for 130 grams of protein or whatever. I’m trying to get the loosened threshold.
Leah
00:15:14 – 00:15:20
That’s true. You’re splitting it into too many meals. You wouldn’t be hitting that losing threshold in most of them. That’s a really great point.
Aidan
00:15:20 – 00:15:47
I think that’s the simplest explanation as to why so basically, losing threshold is basically we’re talking about being like 25 grams to optimise muscle protein synthesis, but it goes hand in hand with, like a certain amount of loose ends. So Lucienne is an amino acid, which is linked to muscle building 25 grams of protein, typically has around enough losing to reach the threshold. Um, so if you spread it out over too many meals, you probably wouldn’t get that unless you raise your total protein and take quite high.
Aidan
00:15:47 – 00:16:14
Because even if you think about your aiming for 200 grams of protein, which is a higher target and you have 10 meals, that’s still only 20 grams of protein per meal, so you probably wouldn’t reach the listing threshold, particularly a plant based diet. The other theory, which I’m not necessarily sold on it seems to have fallen a little bit out of favour. But it’s still like a theory that gets kicked around that might be relevant is this concept of a refractory period, which is basically like you stimulate muscle protein synthesis. It’s rising, it’s rising, it’s rising and then it drops.
Aidan
00:16:14 – 00:16:54
That’s how we maximise this approach. And there’s this thought process that maybe if you stimulate it, it rises. And if you ate again, as it was just about to start dropping, it doesn’t help anymore, like it doesn’t make it continue to rise or whatever. Like it needs a superior to cool down, so to speak or refractory period to go back. So, like Ive away like the losing threshold thing kind of makes a little bit more sense. To me, that’s more clear. Cut the refractory period. Maybe it exists, but like whether or it doesn’t it doesn’t really matter, because it’s like 4 to 6 is. It seems to be optimal. That’s all we need to really think about. Three is almost as good as for if you prefer.
Leah
00:17:01 – 00:17:24
In summary, at the end of the day, you want to focus on getting that total daily protein intake, tick that off and then you want to try to split it between that 4 to 6 meals across the day. And then that’s what’s going to optimise muscle building. And don’t worry about going over that I mean amount that you can optimise muscle proteins, that this is within a single meal because you can absolutely go over that and still build muscle.
Aidan
00:17:24 – 00:17:55
Obviously, great, I just I wouldn’t even think about this upper limit kind of thing. Just focus on those things that you just kind of said. This has been Episode 25 of the ideal nutrition podcast I Want to thank. Once again, everybody is giving us a rating, rating and review. We’re on a little bit of delay in terms of we record these in advance, but what would now be like five or six weeks ago? I asked people on Instagram to give us a rating review and it doubled the amount of reviews we’ve gotten, which was pretty huge and like I was reading through it and I was like, This is pretty cool. It’s pretty cool.
Aidan
00:17:56 – 00:18:10
People are saying some really nice things, and I personally really appreciate that, and I’m sure it does too. So thank you to everybody who left the writing review and thank you to Everybody who listens as well.