Most likely almost all of it, but likely only around ~40 grams (or 0.16 g/lb) would go directly towards muscle protein synthesis and the rest would be absorbed and oxidized to be used as energy.
TL;DR - Excess protein beyond what the body needs can absolutely be oxidized into usable energy and if this results in a significant and consistent excess in metabolizable energy increases in body fat can occur [1-4].
When people are asking this question they are generally really wanting to know how often they need to eat to support muscle growth, so let’s get into that question!
If you would have asked ten years ago what would win for supporting muscle growth
Three meals of 66 grams of protein
Or
Five meals of 40 grams…
I would have absolutely bet a lot of money on the five meal scenario.*
Today, I would bet pretty heavy that if these were whole food meals that it very likely wouldn’t matter.
I would still personally lean towards the five eating occasions of forty grams because I think it maybe might matter over really long times frames for supporting muscle hypertrophy in trained individuals, but given that whole food protein sources are digested and absorbed over 6ish hours it honestly may not matter.
Some science…
“The equivalent of ~0.25 g/kg of leucine-enriched dietary protein in a single meal generally provides a saturating dose of amino acids for the postprandial stimulation of muscle protein synthesis (MPS), which persists for up to 6 hours with the ingestion of whole foods (e.g., egg, beef and dairy proteins). Importantly, after attainment of peak MPS (i.e., ~1.5–3h after protein feeding), MPS gradually reverts back to basal levels even in the presence of sustained plasma aminoacidemia. This is referred to as the “muscle full” effect and demonstrates that there is a refractory period following ingestion of a protein bolus with the MPS pathway not able to be stimulated sequentially for ~3–5 h.”
-Williamson et al., 2021 [5]
Thus, if you ate a big protein meal at 7am, 1pm, and 7pm you would in theory have sufficient protein around for the vast majority of the day to support muscle growth.
It is also key to remember protein intake itself doesn’t independently increase muscle mass, it supports muscle growth and without a training stimulus muscle hypertrophy is not going to occur regardless of how much protein you consume [6, 7].
Now, if you made me bet between two meals of 100 grams of protein or three meals of 66 grams, I would bet on the three meals, but even here the two meals of 100 grams is very likely not going to have as negative of an effect as most people think and it is certainly possible to gain muscle with only two hits of adequate protein in the day [8-11].
And as crazy as it sounds even one meal of 200 grams of whole food protein MAY not even be that big of knock on your gains [12]. I know absolute blasphemy and I am NOT recommending this, but I don’t think it is absolutely catastrophic to one’s ability to build muscle if it is placed somewhere around training.
Hold up, but what about 8 hits of 25 grams?
At this point, I might take 3 hits of 66 or 5 hits of 40 over 8 hits of 25 grams and this is because it looks like MPS might hit its absolute peak at about 40 grams and amino acids (protein) in excess of this may be able to further limit muscle protein breakdown [13-15].
“The amino acids ingested in excess of the saturable dose may not be necessarily “wasted.” Instead, they may suppress protein breakdown to promote a more positive net balance; however, while this has been demonstrated on a whole-body level, it remains an untested hypothesis in the muscle.”
-Hudson et al., 2020 [9]
That said I don’t think it is necessary to go bonkers on protein as 0.8 grams per pound of protein per day is likely more than sufficient to fully support muscle hypertrophy when someone is not in an active fat loss phase and this may kick up to 1.0 to 1.1 grams per pound if someone is looking to lose fat and gain muscle at the same time [16-18]. If we then break this up into four meals of around ~0.2 grams per pound we are probably getting into the theoretical ideal.
“It is argued that a more prudent “muscle-centric” target that maximizes muscle protein synthesis yet minimizes excess amino acid oxidative losses would place a more efficient intake at no more than ∼0.39 g/kg (0.16 g/lb).”
- Moore et al., 2019 [13]
In conclusion, in looking at the bulk of the evidence if you are looking to gain muscle four meals or snacks of at least ~0.16 g/lb of protein is probably a solid play and if you like protein and you go over that it isn’t a big deal.
However, it is good to remember that excess protein can be oxidized into usable energy and if this results in a significant and consistent excess in metabolizable energy increases in body fat can occur [1-4].
*I picked 200 grams for the total protein amount for this article just because the math was easy. If we have a 200 lb male who wanted to lose fat and gain muscle at the same time this is around where we might set their protein amounts. You can check out how much protein you might need for your goal HERE. In a similar scenario for a 150 lb female we might be talking about three eating occasions of 50 grams compared to five eating of 30 grams and all the same arguments would apply because 30 grams is right at 0.2 g/lb for this individual and this amount very very likely tops out MPS. If someone is carrying a significant amount of adipose tissue and is in the overweight or obese category using body weight to calculate protein amounts may get needlessly high, therefore it is likely better to use 1 to 1.5 grams per pound of lean body mass in these scenarios [17, 19]. If you are confused by all these numbers adn acronyms we understand and our My Fit Life coaches are extremely knowledgeable on how to individualize protein amounts to meet your specific goal.
REFERENCES:
1. Bray, G.A., et al., Effect of protein overfeeding on energy expenditure measured in a metabolic chamber. Am J Clin Nutr, 2015. 101(3): p. 496-505.
2. Bray, G.A., et al., Effect of Three Levels of Dietary Protein on Metabolic Phenotype of Healthy Individuals With 8 Weeks of Overfeeding. J Clin Endocrinol Metab, 2016. 101(7): p. 2836-43.
3. Bray, G.A., et al., Effect of dietary protein content on weight gain, energy expenditure, and body composition during overeating: a randomized controlled trial. JAMA, 2012. 307(1): p. 47-55.
4. Jungas, R.L., M.L. Halperin, and J.T. Brosnan, Quantitative analysis of amino acid oxidation and related gluconeogenesis in humans. Physiol Rev, 1992. 72(2): p. 419-48.
5. Williamson, E. and D.R. Moore, A Muscle-Centric Perspective on Intermittent Fasting: A Suboptimal Dietary Strategy for Supporting Muscle Protein Remodeling and Muscle Mass? Front Nutr, 2021. 8: p. 640621.
6. Roth, C., L. Rettenmaier, and M. Behringer, High-Protein Energy-Restriction: Effects on Body Composition, Contractile Properties, Mood, and Sleep in Active Young College Students. Front Sports Act Living, 2021. 3: p. 683327.
7. Backx, E.M., et al., Protein intake and lean body mass preservation during energy intake restriction in overweight older adults. Int J Obes (Lond), 2016. 40(2): p. 299-304.
8. Yasuda, J., et al., Evenly Distributed Protein Intake over 3 Meals Augments Resistance Exercise-Induced Muscle Hypertrophy in Healthy Young Men. J Nutr, 2020. 150(7): p. 1845-1851.
9. Hudson, J.L., R.E.B. Iii, and W.W. Campbell, Protein Distribution and Muscle-Related Outcomes: Does the Evidence Support the Concept? Nutrients, 2020. 12(5).
10. Verboeket-van de Venne, W.P., K.R. Westerterp, and A.D. Kester, Effect of the pattern of food intake on human energy metabolism. Br J Nutr, 1993. 70(1): p. 103-15.
11. Hudson, J.L., et al., Within-day protein distribution does not influence body composition responses during weight loss in resistance-training adults who are overweight. Am J Clin Nutr, 2017. 106(5): p. 1190-1196.
12. Arnal, M.A., et al., Protein feeding pattern does not affect protein retention in young women. J Nutr, 2000. 130(7): p. 1700-4.
13. Moore, D.R., Maximizing Post-exercise Anabolism: The Case for Relative Protein Intakes. Front Nutr, 2019. 6: p. 147.
14. Kim, I.Y., et al., The anabolic response to a meal containing different amounts of protein is not limited by the maximal stimulation of protein synthesis in healthy young adults. Am J Physiol Endocrinol Metab, 2016. 310(1): p. E73-80.
15. Macnaughton, L.S., et al., The response of muscle protein synthesis following whole-body resistance exercise is greater following 40 g than 20 g of ingested whey protein. Physiol Rep, 2016. 4(15).
16. Morton, R.W., et al., A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med, 2018. 52(6): p. 376-384.
17. Longland, T.M., et al., Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss: a randomized trial. Am J Clin Nutr, 2016. 103(3): p. 738-46.
18. Barakat, C., et al., Body Recomposition: Can Trained Individuals Build Muscle and Lose Fat at the Same Time? Journal of Strength and Conditioning Research, 2020. 42(5): p. 7-21.
19. Helms, E.R., et al., A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes. Int J Sport Nutr Exerc Metab, 2014. 24(2): p. 127-38.
About Author: Mario Mendias
