How Much Protein Can The Body Use In A Single Meal For Muscle-Building?

There is controversy about how much protein can be properly utilized by the body per meal for purposes of muscle building.  There is a school of thought that says that, essentially, anything over 20-25 grams per meal will be wasted; on the other hand, bodybuilding tradition advocated considerably higher per meal intakes (leading to much higher per day intakes compared to the typical recommendations).  A study examines the question and comes down on the side supporting the higher levels of protein intake; they write: “The preponderance of data indicate that while consumption of higher protein doses (> 20 g) results in greater AA oxidation, this is not the fate for all the additional ingested AAs as some are utilized for tissue-building purposes. Based on the current evidence, we conclude that to maximize anabolism one should consume protein at a target intake of 0.4 g/kg/meal across a minimum of four meals in order to reach a minimum of 1.6 g/kg/day. Using the upper daily intake of 2.2 g/kg/day reported in the literature spread out over the same four meals would necessitate a maximum of 0.55 g/kg/meal.”  Abstract:

Controversy exists about the maximum amount of protein that can be utilized for lean tissue-building purposes in a single meal for those involved in regimented resistance training. It has been proposed that muscle protein synthesis is maximized in young adults with an intake of ~ 20-25 g of a high-quality protein; anything above this amount is believed to be oxidized for energy or transaminated to form urea and other organic acids. However, these findings are specific to the provision of fast-digesting proteins without the addition of other macronutrients. Consumption of slower-acting protein sources, particularly when consumed in combination with other macronutrients, would delay absorption and thus conceivably enhance the utilization of the constituent amino acids. The purpose of this paper was twofold: 1) to objectively review the literature in an effort to determine an upper anabolic threshold for per-meal protein intake; 2) draw relevant conclusions based on the current data so as to elucidate guidelines for per-meal daily protein distribution to optimize lean tissue accretion. Both acute and long-term studies on the topic were evaluated and their findings placed into context with respect to per-meal utilization of protein and the associated implications to distribution of protein feedings across the course of a day. The preponderance of data indicate that while consumption of higher protein doses (> 20 g) results in greater AA oxidation, this is not the fate for all the additional ingested AAs as some are utilized for tissue-building purposes. Based on the current evidence, we conclude that to maximize anabolism one should consume protein at a target intake of 0.4 g/kg/meal across a minimum of four meals in order to reach a minimum of 1.6 g/kg/day. Using the upper daily intake of 2.2 g/kg/day reported in the literature spread out over the same four meals would necessitate a maximum of 0.55 g/kg/meal.

This conclusion is supported by this other study, which also advocates higher per meal protein intakes.

Please note that this advice – from these studies and not from this blog – deals with effects on muscle building and not overall health.  Whether or not additional protein intake is good for you is something that you need to determine in conjunction with your physician, nutritionist, etc.  For example, people with kidney problems or some digestive disorders probably should not be consuming this much protein, and then there is the issue of how much saturated fat is being consumed, if animal proteins are utilized.

So what is best for muscle building and what is best for overall health are not the same thing.