7 ms·

Anabolic response to protein ingestion has no upper limit in humans

39 points by henning 3y ago

jaggs 3y ago
[flagged]
henning 3y ago
Apologies for only linking to the abstract. PDF can be found here: https://www.cell.com/cell-reports-medicine/pdfExtended/S2666-3791(23)00540-2 https://www.cell.com/cell-reports-medicine/pdfExtended/S2666...
- guerrilla 3y ago
  Wait, how do they conclude "no upper limit" from 100g? The conclusion seems to say rather that we can do at least 100g. Did I miss something?
thriftwy 3y ago
Now, find a way to trigger that without excercise @ win your Nobel prize. Before anybody intervenes, I want to say that excercise is stupid activity and that gorillas don't excercise that much. Try wrestle with one.
- silverquiet 3y ago
  I'm pretty sure they're called steroids and while they work better if you exercise, that isn't a requirement.
  - thriftwy 3y ago
    I've heard they're not that healthy. Gorillas on the other hand are. I wonder if there's some floor dosage which is far from affecting your health but already significant in affecting your well-being. Why aren't we all on steroids. Why people who are trying to get rid of fat are not on steroids.
    - loeg 3y ago
      > I've heard they're not that healthy. Gorillas on the other hand are. Are they? Gorillas live to 35-40. Humans live to 80+.
    - silverquiet 3y ago
      I suspect that bodybuilding is unhealthy for a number of reasons and is obviously associated with steroid use. It seems possible to me (and I really don't know that much here) that some amount of steroid use may possibly increase health, but that is not what bodybuilders are interested in. Either way, I do not take them.
      - loeg 3y ago
        The vast majority of competitive bodybuilders are on very high doses of anabolic steroids (AAS) and compete in an "open" (untested) league. Absurdly high dose AAS use is associated with (at least) a couple kinds of heart disease. It's not good for you. (There are also some "natural" bodybuilders and a smaller tested/natural league.)
    - FredPret 3y ago
      Why are gorillas healthy? They aren't getting diabetes, sure, but most wild animals teeter on the edge of survival all the time - not a state of vibrant health.
    - AmericanChopper 3y ago
      > Why people who are trying to get rid of fat are not on steroids. A lot of people are. Anavar and Clenbuterol is a very popular fat loss regimen (though likely not acquired via a legitimate prescription very often), and not just for bodybuilders. The amount of middle age men on Testosterone Replacement Therapy is also likely a lot higher than you think it is, and body fat management is one of the more appealing benefits of TRT. The risks of messing with your natural sex hormones never go away though, so there’s always going to be risks that a lot of people don’t want to take. Like high blood pressure, heart disease, suppression of natural testosterone production, hypogonadism (and infertility), gynecomastia… and for women there’s the androgenising effects, as steroids are part of the pharmaceutical side of a gender reassignment for them (which is why it’s not uncommon for some of the larger female bodybuilders to have especially deep voices, or even masculine-looking facial hair).
- jagraff 3y ago
  Gorillas don't sit at a desk 8 hours a day
  - tandr 3y ago
    So you haven't seen me WFH yet... phew
  - thriftwy 3y ago
    They lay under a tree for 12. They aren't that physically active unless they must.
  - jerf 3y ago
    Gorillas aren't just "a bit strong" such that it could be explained by different exercise routines; they're stronger than world-class weightlifters. They're not strong because they don't sit at desks, they're strong because their bodies are tuned for strength and because they don't route as much energy to their brains. Contrary to a lot of nature documentaries, homo sapiens has quite a lot of advantages; well above average vision, exquisite muscular control, quite excellent hearing, almost unmatched vocalization abilities, and of course, the supernal brain, among many other attributes of note. But we do quite literally punch well below our weight, by any metric; body size, muscle mass, etc. The sci-fi trope of human being weaker than orcs, weaker than Vulcans, weaker than Klingons, etc. actually has some basis in fact.
    - FredPret 3y ago
      We're the toughest of the land animals, by far. The only land animals that can match us for endurance are certain breeds of horses and dogs, because we bred them specifically to keep up with us. There are lots of tribes around the world whose hunting tactic is to walk at a particular deer until it falls over dead. We also have really good immune systems, giving us the ability to live all over the world in various filthy conditions without immediately dying from infection. And our digestive systems are very flexible. Some prehistoric people were completely vegeterian, some lived entirely off of fish, etc. Show me an animal that can do all that.
- tanbog5 3y ago
  Why would you compare the upper body strength of a human to an primate that evolved to have high upper body strength? I would rather run a marathon against one.
- rschiavone 3y ago
  Gorillas lack myostatin, a protein that inhibits muscle growth in us humans.
  - thriftwy 3y ago
    I wonder what happens if we would break this protein, such as by erasing its start codon. Will we get gorilla strength (and appetite, which is also a good thing in XXI?) I bet somebody out there already has this mutation.
- steve_adams_86 3y ago
  Surviving is exercise for a gorilla. They carry their mass around, climb with it, occasionally compete with other gorillas, etc. It's also key to consider that they're genetically programmed to develop more muscle mass with relatively large amounts of rest and no need to explicitly work out. Humans have survived in less abundant conditions, with leaner times and lower energy requirements. We've adapted to sacrifice mass and strength at times. In order to develop strength, we need to do hard work. While we're remarkably similar to gorillas, this is one way in which we differ quite a bit.
  - thriftwy 3y ago
    > We've adapted to sacrifice mass and strength at times. Can we please find a way to un-sacrifice mass, un-fit to survive in less abundant conditions? Right now, the food is so abundant it is actively killing us. But we are fat and not muscular. Are we sentient species, after all? I do not joke when I say it would be multiple Nobel prizes. Everybody will get around five quality-adjusted life years on average if you do it correctly.
    - simmerup 3y ago
      Arguably it’s the ultra processed food that’s killing us. Some studies show that when we eat whole foods our bodies generally maintain healthy weights
      - steve_adams_86 3y ago
        > Some studies show that when we eat whole foods our bodies generally maintain healthy weights I wonder if it's because it's harder (though not impossible) to eat too much of a well-balanced, whole-food diet.
        simmerup 3y ago
        It’s true, but why is it harder? Why is 500g of frozen pizza made up of modified starches and sugary sauce easier to eat and less filling than 500g of sourdough pizza of whole grains and real cheese/tomato Maybe because our body is better equipped to register the calorie intake from the real food
- FredPret 3y ago
  Not a biologist, but - put that gorilla on a squat program with a couple gallons of milk a day and he'll be even more muscular.
  - bentt 3y ago
    Risking downvotes but pretty sick nocontext
    - simmerup 3y ago
      Think we need an AI that auto hides reddit references
- pawelduda 3y ago
  Maybe ask gorillas how they trigger that without exercise if they're so cool /s before anyone intervenes
- cmrdporcupine 3y ago
  > Try wrestle with one. I'd rather snuggle.
- deleted 3y ago
  [deleted]
- Tommstein 3y ago
  At the risk of blowing your mind, you are not a gorilla.
  - thriftwy 3y ago
    I am a human capable of editing its own genome, so theoretically I can be anything.
    - Tommstein 3y ago
      When you successfully edit your genome and turn into a gorilla, then you will be a gorilla. Until then, you are not a gorilla.
datadrivenangel 3y ago
This validates the approach of eating a ludicrous quantity of protein after working out.
- ano-ther 3y ago
  Indeed. Milk has 3.4g protein per 100g. In the study they fed 100g of protein, which was "the largest amount of protein that we consider feasible to consume in a single meal (100 g)". It is the equivalent of drinking 3 liters of milk.
  - brcmthrowaway 3y ago
    or 4 scoops of whey protein isolate
  - datadrivenangel 3y ago
    Eating 500g of chicken breast is 150g of protein, and that's not an infeasible amount of chicken to eat.
  - mmh0000 3y ago
    Milk is a terrible source of protein generally. And it has a ton of fat. There are exceptions, like, Fairlife milk that doubles the protein content. 2 scoops of Powered Pea Protein is my favorite, go-to choice.
    - ruthie_cohen 3y ago
      Whey Protein, Casein Protein or Whey Protein Isolate is a more like-for-like replacement for milk than a plant based alternative. There’s also nothing inherently wrong with consuming fat, it’s more than twice the energy per gram compared to carbs and protein. If you are bulking or need to consume more calories, there’s no issue with drinking milk or using it in smoothies.
- SoftTalker 3y ago
  Yeah my custom has been a 25g protein drink immediately after a workout I might try bumping that up.
natbennett 3y ago
Oh this is very cool. It seems like the takeaway for body builders is “you don’t actually have to time protein ingestion super carefully?”
- dools 3y ago
  I think it makes no sense that one would need to time protein intake. After all the way muscle grows is in response to damage after use. We don’t worry about a “calcium window” when we break a bone.
- ensacco 3y ago
  Not from what I can tell. There still seems to be a spike in anabolic response shortly after ingestion that curtails over the course of the following 12 hours, with a 2-3 hour window holding the most concentration of lysine/most other amino acids. From what I've read, my key take-away is that the previously assumed limits of protein ingestion aren't as low as this study suggests. Though, it's worth pointing out that protein consumption in this trial was 0g, 25g and 100g, missing the ~50g mark* that most bodybuilders assumed to be the cap. *edit: or, 0.25g per lb of bodyweight
turkeygizzard 3y ago
Wow, I've only read the abstract so far but this basically goes against all conventional research on this topic AFAIK. I read probably ~50 papers on this topic (maximal protein dosing) and emailed a few researchers about it as I was writing a book. I believe the saturation point for a relative dose for a single meal is generally held to be ~0.25g per kg of bodyweight. Of course, there are some obvious observable issues with this belief given that there are people who practice intermittent fasting and have no issues building muscle, so it'll be really interesting to see if this study replicates EDIT: After skimming the paper, I don't see anything immediately wrong with it. But there are some important nuances to note: the subjects were all fasted and given milk protein (casein in milk protein is known to take longer to absorb than pure whey protein which is a popular choice for these studies), and the measurements were made after an hour of exercise. This would skew the results towards more protein sensitivity than in normal settings where a person is pretty much always somewhat well-fed and not always eating after exercise. This is still encouraging because the results for post-exercise protein metabolism have still indicated a much lower limit than a 100g dose. Their report that oxidation rates didn't increase significantly is also notable since the belief has generally been that excess protein is oxidized and burned for energy instead of being incorporated into muscle. However, it would've been nice for them to include a 50g group as well to see if the dose-response relationship was really still linear between 25-50-100 Ultimately, this result seems encouraging for increasing post-exercise protein consumption for muscle gain, but we shouldn't discount the fact that the subjects were fasted before exercise. It would be interesting to see this study prolonged over the course of a day with further protein ingestions to see if the area-under-the-curve of muscle protein synthesis would eventually equalize in both groups, or if the larger immediately-post-exercise dose made a lasting difference. Existing research seems to not indicate such an "anabolic window". I might speculate that there is a daily limit for protein ingestion, but it doesn't matter if you hit that limit in one meal or five. That said, I have previously come across a paper that found medium-sized, spaced out doses to be more effective than infrequent large doses and overly frequent small doses, so there's still more to discover here
- brcmthrowaway 3y ago
  book link?
funnyenough 3y ago
bros were right.
- AmericanChopper 3y ago
  I don’t think this should be surprising. Traditional knowledge (which I would group bro-science under) contains a lot of legitimate insights. Bro scientists are focused on getting measurable results, and they know when they achieve that. The main downsides of their lack of rigour are that they don’t have very good mechanisms for eliminating useless superstitions, and of course the lack of safety controls in their experiments (which I think most of them probably understand and accept). Sumerian shamans were also right about chewing willow bark (along with countless other examples of that sort of thing).
ericra 3y ago
Really surprising stuff (to me). I'm coming from the prior that large amounts of protein ingestion in one sitting are "wasted" and do not contribute much above a certain moderate amount. This is obviously only a single study, but it at least opened me up more to the possibility that this is wrong. Some important limitations as listed in the paper: - Study only assessed a short-term assessment window (~12 hr), and the researchers speculate that metabolic changes over time might skew these results: "it is possible that the metabolic response to protein ingestion is modified over time. For example, it could be speculated that amino acid oxidation may increase in response to frequent, prolonged epi- sodes of hyperaminoacidemia or that large postprandial protein gains are compensated for by upregulation of amino acid oxida- tion in a subsequent fasted state" - Study was with healthy young men after a bout of whole-body resistance exercise. May not extrapolate to other populations or conditions (i.e. at rest). - Other study "limitations" point out that they were conservative in their conclusions, and the results of eating large amounts of protein at one time may be even stronger than stated in the paper. Still, very interesting stuff.
raverbashing 3y ago
Just to be clear, 100g is a large dose, but far from being able to assert there's "no upper limit"
HellsMaddy 3y ago
While this might sound like good evidence to support increasing your protein intake to build more muscle, it doesn't take into account the adverse effects of protein intake above the RDA of ~0.8g/kg of healthy body weight, unless you're over 65. > The adverse effects associated with long-term high protein/high meat intake in humans were (a) disorders of bone and calcium homeostasis, (b) disorders of renal function, (c) increased cancer risk, (d) disorders of liver function, and (e) precipitated progression of coronary artery disease. - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4045293/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4045293/ High protein intake is associated with elevated levels of IGF-1, and "High IGF-1 levels increased the relationship between mortality and high protein": > Respondents aged 50–65 reporting high protein intake had a 75% increase in overall mortality and a 4-fold increase in cancer death risk during the following 18 years. These associations were either abolished or attenuated if the proteins were plant derived. Conversely, high protein intake was associated with reduced cancer and overall mortality in respondents over 65, but a 5-fold increase in diabetes mortality across all ages. > These results suggest that low protein intake during middle age followed by moderate to high protein consumption in old adults may optimize healthspan and longevity. - https://www.cell.com/fulltext/S1550-4131(14)00062-X https://www.cell.com/fulltext/S1550-4131(14)00062-X Also important to note that one of the authors of the OP article is an employee of FrieslandCampina, the world's largest dairy co-operative and one of the top 5 dairy companies in the world.
- sk11001 3y ago
  A lot of these studies are observational including every single one of the cancer studies cited, and it's very difficult to separate high-calorie intake from high-protein intake. In the general population the group who eats a lot of protein overlaps a lot with the group who eats too much food in general and that excess in caloric intake is much more likely to be the cause of health problems than the protein intake.
- spreadlove5683 3y ago
  Does this apply to people who are weightlifting too though?
coldtea 3y ago
"Anabolic response to protein ingestion has no upper limit in humans - according to a single paper, that might not replicate and be full of methodology errors and/or conflicts of interest, time will tell..." Here's a better title, before people start jumping to conclusion about how this "invalidates conventional research" or how they'll start following this, etc.
lumb63 3y ago
I’ve been weight training consistently for more than a decade, keep up to date on the science, and I don’t find this that surprising. mTOR is stimulated by a rising plasma concentration of leucine. It can only be stimulated to a certain extent at a given time (known as the “muscle full” effect), but if the leucine level remains chronically elevated until after the refractory period, it makes sense that another bout would trigger. You can even see in their results that the smaller protein feeding produced a larger percentage-wise incorporation of that protein into muscle protein (17% vs 13%). If the subjects consumed that 25g four times across the 12 hours, I imagine they would have produced a larger net accumulation of muscle protein than the 100g group. This is because each discrete feeding could produce other anabolic effects, such as stimulating the release of insulin. You can also see that the 25g dosing was insufficient to saturate even short-term muscle protein synthesis rates from figure 6C. Based on that graph, I’d guess that about a 40g bolus would have been sufficient. So, no groundbreaking practical implications, IMO. Single bolus is still suboptimal, just maybe less suboptimal than the researchers thought. When evaluating practical implications, it is also worth noting that most humans do not fast after consuming a single protein shake, or after consuming four protein shakes. Our diets are typically a little more complex and varied than that.
rajnathani 3y ago
> we show that the ingestion of 100 g protein results in a greater and more prolonged (>12 h) anabolic response when compared to the ingestion of 25 g protein So the 25g protein group didn't consume any more protein/meal within 12h post-workout after their 25g protein meal? This seems like a hole in the study.
maxglute 3y ago
>100 g protein results in a greater and more prolonged (>12 h) anabolic response when compared to the ingestion of 25 g protein. What does this even mean? Are subjects taking 100g and 25g of protein a day? Or 200g and 100g over 2 meals?

39 points by henning 3y ago

[flagged]

Apologies for only linking to the abstract. PDF can be found here: https://www.cell.com/cell-reports-medicine/pdfExtended/S2666-3791(23)00540-2 https://www.cell.com/cell-reports-medicine/pdfExtended/S2666...

guerrilla 3y ago
Wait, how do they conclude "no upper limit" from 100g? The conclusion seems to say rather that we can do at least 100g. Did I miss something?

thriftwy 3y ago

Now, find a way to trigger that without excercise @ win your Nobel prize. Before anybody intervenes, I want to say that excercise is stupid activity and that gorillas don't excercise that much. Try wrestle with one.

silverquiet 3y ago
I'm pretty sure they're called steroids and while they work better if you exercise, that isn't a requirement.
- thriftwy 3y ago
  I've heard they're not that healthy. Gorillas on the other hand are. I wonder if there's some floor dosage which is far from affecting your health but already significant in affecting your well-being. Why aren't we all on steroids. Why people who are trying to get rid of fat are not on steroids.
  - loeg 3y ago
    > I've heard they're not that healthy. Gorillas on the other hand are. Are they? Gorillas live to 35-40. Humans live to 80+.
  - silverquiet 3y ago
    I suspect that bodybuilding is unhealthy for a number of reasons and is obviously associated with steroid use. It seems possible to me (and I really don't know that much here) that some amount of steroid use may possibly increase health, but that is not what bodybuilders are interested in. Either way, I do not take them.
    - loeg 3y ago
      The vast majority of competitive bodybuilders are on very high doses of anabolic steroids (AAS) and compete in an "open" (untested) league. Absurdly high dose AAS use is associated with (at least) a couple kinds of heart disease. It's not good for you. (There are also some "natural" bodybuilders and a smaller tested/natural league.)
  - FredPret 3y ago
    Why are gorillas healthy? They aren't getting diabetes, sure, but most wild animals teeter on the edge of survival all the time - not a state of vibrant health.
  - AmericanChopper 3y ago
    > Why people who are trying to get rid of fat are not on steroids. A lot of people are. Anavar and Clenbuterol is a very popular fat loss regimen (though likely not acquired via a legitimate prescription very often), and not just for bodybuilders. The amount of middle age men on Testosterone Replacement Therapy is also likely a lot higher than you think it is, and body fat management is one of the more appealing benefits of TRT. The risks of messing with your natural sex hormones never go away though, so there’s always going to be risks that a lot of people don’t want to take. Like high blood pressure, heart disease, suppression of natural testosterone production, hypogonadism (and infertility), gynecomastia… and for women there’s the androgenising effects, as steroids are part of the pharmaceutical side of a gender reassignment for them (which is why it’s not uncommon for some of the larger female bodybuilders to have especially deep voices, or even masculine-looking facial hair).
jagraff 3y ago
Gorillas don't sit at a desk 8 hours a day
- tandr 3y ago
  So you haven't seen me WFH yet... phew
- thriftwy 3y ago
  They lay under a tree for 12. They aren't that physically active unless they must.
- jerf 3y ago
  Gorillas aren't just "a bit strong" such that it could be explained by different exercise routines; they're stronger than world-class weightlifters. They're not strong because they don't sit at desks, they're strong because their bodies are tuned for strength and because they don't route as much energy to their brains. Contrary to a lot of nature documentaries, homo sapiens has quite a lot of advantages; well above average vision, exquisite muscular control, quite excellent hearing, almost unmatched vocalization abilities, and of course, the supernal brain, among many other attributes of note. But we do quite literally punch well below our weight, by any metric; body size, muscle mass, etc. The sci-fi trope of human being weaker than orcs, weaker than Vulcans, weaker than Klingons, etc. actually has some basis in fact.
  - FredPret 3y ago
    We're the toughest of the land animals, by far. The only land animals that can match us for endurance are certain breeds of horses and dogs, because we bred them specifically to keep up with us. There are lots of tribes around the world whose hunting tactic is to walk at a particular deer until it falls over dead. We also have really good immune systems, giving us the ability to live all over the world in various filthy conditions without immediately dying from infection. And our digestive systems are very flexible. Some prehistoric people were completely vegeterian, some lived entirely off of fish, etc. Show me an animal that can do all that.
tanbog5 3y ago
Why would you compare the upper body strength of a human to an primate that evolved to have high upper body strength? I would rather run a marathon against one.
rschiavone 3y ago
Gorillas lack myostatin, a protein that inhibits muscle growth in us humans.
- thriftwy 3y ago
  I wonder what happens if we would break this protein, such as by erasing its start codon. Will we get gorilla strength (and appetite, which is also a good thing in XXI?) I bet somebody out there already has this mutation.
steve_adams_86 3y ago
Surviving is exercise for a gorilla. They carry their mass around, climb with it, occasionally compete with other gorillas, etc. It's also key to consider that they're genetically programmed to develop more muscle mass with relatively large amounts of rest and no need to explicitly work out. Humans have survived in less abundant conditions, with leaner times and lower energy requirements. We've adapted to sacrifice mass and strength at times. In order to develop strength, we need to do hard work. While we're remarkably similar to gorillas, this is one way in which we differ quite a bit.
- thriftwy 3y ago
  > We've adapted to sacrifice mass and strength at times. Can we please find a way to un-sacrifice mass, un-fit to survive in less abundant conditions? Right now, the food is so abundant it is actively killing us. But we are fat and not muscular. Are we sentient species, after all? I do not joke when I say it would be multiple Nobel prizes. Everybody will get around five quality-adjusted life years on average if you do it correctly.
  - simmerup 3y ago
    Arguably it’s the ultra processed food that’s killing us. Some studies show that when we eat whole foods our bodies generally maintain healthy weights
    - steve_adams_86 3y ago
      > Some studies show that when we eat whole foods our bodies generally maintain healthy weights I wonder if it's because it's harder (though not impossible) to eat too much of a well-balanced, whole-food diet.
      - simmerup 3y ago
        It’s true, but why is it harder? Why is 500g of frozen pizza made up of modified starches and sugary sauce easier to eat and less filling than 500g of sourdough pizza of whole grains and real cheese/tomato Maybe because our body is better equipped to register the calorie intake from the real food
FredPret 3y ago
Not a biologist, but - put that gorilla on a squat program with a couple gallons of milk a day and he'll be even more muscular.
- bentt 3y ago
  Risking downvotes but pretty sick nocontext
  - simmerup 3y ago
    Think we need an AI that auto hides reddit references
pawelduda 3y ago
Maybe ask gorillas how they trigger that without exercise if they're so cool /s before anyone intervenes
cmrdporcupine 3y ago
> Try wrestle with one. I'd rather snuggle.
deleted 3y ago
[deleted]
Tommstein 3y ago
At the risk of blowing your mind, you are not a gorilla.
- thriftwy 3y ago
  I am a human capable of editing its own genome, so theoretically I can be anything.
  - Tommstein 3y ago
    When you successfully edit your genome and turn into a gorilla, then you will be a gorilla. Until then, you are not a gorilla.

datadrivenangel 3y ago

This validates the approach of eating a ludicrous quantity of protein after working out.

ano-ther 3y ago
Indeed. Milk has 3.4g protein per 100g. In the study they fed 100g of protein, which was "the largest amount of protein that we consider feasible to consume in a single meal (100 g)". It is the equivalent of drinking 3 liters of milk.
- brcmthrowaway 3y ago
  or 4 scoops of whey protein isolate
- datadrivenangel 3y ago
  Eating 500g of chicken breast is 150g of protein, and that's not an infeasible amount of chicken to eat.
- mmh0000 3y ago
  Milk is a terrible source of protein generally. And it has a ton of fat. There are exceptions, like, Fairlife milk that doubles the protein content. 2 scoops of Powered Pea Protein is my favorite, go-to choice.
  - ruthie_cohen 3y ago
    Whey Protein, Casein Protein or Whey Protein Isolate is a more like-for-like replacement for milk than a plant based alternative. There’s also nothing inherently wrong with consuming fat, it’s more than twice the energy per gram compared to carbs and protein. If you are bulking or need to consume more calories, there’s no issue with drinking milk or using it in smoothies.
SoftTalker 3y ago
Yeah my custom has been a 25g protein drink immediately after a workout I might try bumping that up.

natbennett 3y ago

Oh this is very cool. It seems like the takeaway for body builders is “you don’t actually have to time protein ingestion super carefully?”

dools 3y ago
I think it makes no sense that one would need to time protein intake. After all the way muscle grows is in response to damage after use. We don’t worry about a “calcium window” when we break a bone.
ensacco 3y ago
Not from what I can tell. There still seems to be a spike in anabolic response shortly after ingestion that curtails over the course of the following 12 hours, with a 2-3 hour window holding the most concentration of lysine/most other amino acids. From what I've read, my key take-away is that the previously assumed limits of protein ingestion aren't as low as this study suggests. Though, it's worth pointing out that protein consumption in this trial was 0g, 25g and 100g, missing the ~50g mark* that most bodybuilders assumed to be the cap. *edit: or, 0.25g per lb of bodyweight

turkeygizzard 3y ago

Wow, I've only read the abstract so far but this basically goes against all conventional research on this topic AFAIK. I read probably ~50 papers on this topic (maximal protein dosing) and emailed a few researchers about it as I was writing a book. I believe the saturation point for a relative dose for a single meal is generally held to be ~0.25g per kg of bodyweight. Of course, there are some obvious observable issues with this belief given that there are people who practice intermittent fasting and have no issues building muscle, so it'll be really interesting to see if this study replicates EDIT: After skimming the paper, I don't see anything immediately wrong with it. But there are some important nuances to note: the subjects were all fasted and given milk protein (casein in milk protein is known to take longer to absorb than pure whey protein which is a popular choice for these studies), and the measurements were made after an hour of exercise. This would skew the results towards more protein sensitivity than in normal settings where a person is pretty much always somewhat well-fed and not always eating after exercise. This is still encouraging because the results for post-exercise protein metabolism have still indicated a much lower limit than a 100g dose. Their report that oxidation rates didn't increase significantly is also notable since the belief has generally been that excess protein is oxidized and burned for energy instead of being incorporated into muscle. However, it would've been nice for them to include a 50g group as well to see if the dose-response relationship was really still linear between 25-50-100 Ultimately, this result seems encouraging for increasing post-exercise protein consumption for muscle gain, but we shouldn't discount the fact that the subjects were fasted before exercise. It would be interesting to see this study prolonged over the course of a day with further protein ingestions to see if the area-under-the-curve of muscle protein synthesis would eventually equalize in both groups, or if the larger immediately-post-exercise dose made a lasting difference. Existing research seems to not indicate such an "anabolic window". I might speculate that there is a daily limit for protein ingestion, but it doesn't matter if you hit that limit in one meal or five. That said, I have previously come across a paper that found medium-sized, spaced out doses to be more effective than infrequent large doses and overly frequent small doses, so there's still more to discover here

brcmthrowaway 3y ago
book link?

funnyenough 3y ago

bros were right.

AmericanChopper 3y ago
I don’t think this should be surprising. Traditional knowledge (which I would group bro-science under) contains a lot of legitimate insights. Bro scientists are focused on getting measurable results, and they know when they achieve that. The main downsides of their lack of rigour are that they don’t have very good mechanisms for eliminating useless superstitions, and of course the lack of safety controls in their experiments (which I think most of them probably understand and accept). Sumerian shamans were also right about chewing willow bark (along with countless other examples of that sort of thing).

ericra 3y ago

Really surprising stuff (to me). I'm coming from the prior that large amounts of protein ingestion in one sitting are "wasted" and do not contribute much above a certain moderate amount. This is obviously only a single study, but it at least opened me up more to the possibility that this is wrong. Some important limitations as listed in the paper: - Study only assessed a short-term assessment window (~12 hr), and the researchers speculate that metabolic changes over time might skew these results: "it is possible that the metabolic response to protein ingestion is modified over time. For example, it could be speculated that amino acid oxidation may increase in response to frequent, prolonged epi- sodes of hyperaminoacidemia or that large postprandial protein gains are compensated for by upregulation of amino acid oxida- tion in a subsequent fasted state" - Study was with healthy young men after a bout of whole-body resistance exercise. May not extrapolate to other populations or conditions (i.e. at rest). - Other study "limitations" point out that they were conservative in their conclusions, and the results of eating large amounts of protein at one time may be even stronger than stated in the paper. Still, very interesting stuff.

raverbashing 3y ago

Just to be clear, 100g is a large dose, but far from being able to assert there's "no upper limit"

HellsMaddy 3y ago

While this might sound like good evidence to support increasing your protein intake to build more muscle, it doesn't take into account the adverse effects of protein intake above the RDA of ~0.8g/kg of healthy body weight, unless you're over 65. > The adverse effects associated with long-term high protein/high meat intake in humans were (a) disorders of bone and calcium homeostasis, (b) disorders of renal function, (c) increased cancer risk, (d) disorders of liver function, and (e) precipitated progression of coronary artery disease. - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4045293/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4045293/ High protein intake is associated with elevated levels of IGF-1, and "High IGF-1 levels increased the relationship between mortality and high protein": > Respondents aged 50–65 reporting high protein intake had a 75% increase in overall mortality and a 4-fold increase in cancer death risk during the following 18 years. These associations were either abolished or attenuated if the proteins were plant derived. Conversely, high protein intake was associated with reduced cancer and overall mortality in respondents over 65, but a 5-fold increase in diabetes mortality across all ages. > These results suggest that low protein intake during middle age followed by moderate to high protein consumption in old adults may optimize healthspan and longevity. - https://www.cell.com/fulltext/S1550-4131(14)00062-X https://www.cell.com/fulltext/S1550-4131(14)00062-X Also important to note that one of the authors of the OP article is an employee of FrieslandCampina, the world's largest dairy co-operative and one of the top 5 dairy companies in the world.

sk11001 3y ago
A lot of these studies are observational including every single one of the cancer studies cited, and it's very difficult to separate high-calorie intake from high-protein intake. In the general population the group who eats a lot of protein overlaps a lot with the group who eats too much food in general and that excess in caloric intake is much more likely to be the cause of health problems than the protein intake.
spreadlove5683 3y ago
Does this apply to people who are weightlifting too though?

coldtea 3y ago

"Anabolic response to protein ingestion has no upper limit in humans - according to a single paper, that might not replicate and be full of methodology errors and/or conflicts of interest, time will tell..." Here's a better title, before people start jumping to conclusion about how this "invalidates conventional research" or how they'll start following this, etc.

lumb63 3y ago

I’ve been weight training consistently for more than a decade, keep up to date on the science, and I don’t find this that surprising. mTOR is stimulated by a rising plasma concentration of leucine. It can only be stimulated to a certain extent at a given time (known as the “muscle full” effect), but if the leucine level remains chronically elevated until after the refractory period, it makes sense that another bout would trigger. You can even see in their results that the smaller protein feeding produced a larger percentage-wise incorporation of that protein into muscle protein (17% vs 13%). If the subjects consumed that 25g four times across the 12 hours, I imagine they would have produced a larger net accumulation of muscle protein than the 100g group. This is because each discrete feeding could produce other anabolic effects, such as stimulating the release of insulin. You can also see that the 25g dosing was insufficient to saturate even short-term muscle protein synthesis rates from figure 6C. Based on that graph, I’d guess that about a 40g bolus would have been sufficient. So, no groundbreaking practical implications, IMO. Single bolus is still suboptimal, just maybe less suboptimal than the researchers thought. When evaluating practical implications, it is also worth noting that most humans do not fast after consuming a single protein shake, or after consuming four protein shakes. Our diets are typically a little more complex and varied than that.

rajnathani 3y ago

> we show that the ingestion of 100 g protein results in a greater and more prolonged (>12 h) anabolic response when compared to the ingestion of 25 g protein So the 25g protein group didn't consume any more protein/meal within 12h post-workout after their 25g protein meal? This seems like a hole in the study.

maxglute 3y ago

>100 g protein results in a greater and more prolonged (>12 h) anabolic response when compared to the ingestion of 25 g protein. What does this even mean? Are subjects taking 100g and 25g of protein a day? Or 200g and 100g over 2 meals?