Bodybuilders, athletes, and fitness enthusiasts alike love protein because it is beneficial for muscle growth. But, how much protein can your body actually absorb at once?
Lots of controversy surrounds this subject, some people say there is no limit, and some people say there’s a very low limit. However, the research has drawn some conclusions on this matter.
The amount of protein that the body can absorb at once is limited. In the case of a quickly absorbing protein, like whey protein, it is around 8-10 grams of protein absorbed per hour, you shouldn’t consume more than 25-30 grams of protein per meal.
In this article, I’ll explain the most optimal amount of protein you should be consuming per day, what happens to excess protein and why protein absorption matters.
Table of Contents:
- How much protein can you absorb in one go?
- What happens to excess protein consumption?
- How much protein to consume per day
How Much Protein Can You Absorb In One Go?
The proposed hypothesis is that consuming beyond around 20 grams of protein in one go results in greater amino acid oxidation than consuming lower amounts.
Meaning that you would be better off consuming less protein but more often, compared to consuming more protein but less often.
One study examined exactly this, the study consisted of 3 groups:
- 8 servings of 10 grams whey protein every 1.5 hours
- 4 servings of 20 grams whey protein every 3 hours
- 2 servings of 40 grams whey protein every 6 hours
The results of this study revealed that muscle protein synthesis was highest in individuals who had four servings of 20 grams of whey protein.
When the larger 40 grams dosage was consumed, no further benefit was shown, and in fact, a lesser increase in muscle protein synthesis was observed.
But, that still doesn’t answer the question of how much protein can be absorbed in one go, below I’ll go into more detail and explain the answer to this question.
Most of the protein we eat and consume is absorbed, it just doesn’t all go towards building muscle, some of the amino acids within the protein are oxidised for energy.
Research shows that amino acid oxidation increases significantly when consuming beyond 20 grams of protein in one go. (Source)
Meaning any protein consumed beyond 20 grams will begin to be broken down for energy instead of being used for building and repairing muscle.
However, this doesn’t mean that the limit of protein absorption in one go is 20 grams, it simply means beyond this the effects of protein towards muscle building begin to get less and less.
Based on the study conducted above and the research on amino acid oxidation, most of the protein we eat is absorbed, beyond 20 grams it begins to be used for energy, meaning that 20-30 grams, split 4-5 times per day is the optimal amount of protein to consume.
What Happens to Excess Protein Consumption?
When you consume protein it goes through the stomach and intestines, from there a certain amount is absorbed per hour, around 8-10 grams per hour, almost all protein is absorbed.
Depending on the amount of protein ingested, different processes happen.
When you approach around 20 grams of protein in one go, some of the protein ingested will undergo a process known as amino acid oxidation, being converted and used for energy.
Around 25 grams of ingested protein, a significant portion of that protein will no longer be used for building muscle.
Around 30 grams of protein in one go seems to maximally stimulate muscle protein synthesis, any more seems to have minimal to no additional benefit for building muscle.
How Much Protein to Consume per Day
Research shows conflicting results, but unravelling it all reveals the answers we want, below I break down the studies in order to answer how much protein we should really be consuming.
The measurements of protein intake is usually in the form of g/kg, for example; 1 g/kg means that you should aim to consume 1 gram of protein per 1 kg of body weight.
- The minimal quantity of protein required is 0.8 g/kg
- The RDA of protein is 1 g/kg for healthy people, for the elderly it is 1.2 g/kg
- The optimal amount of protein per day is around 1.6 g/kg
- The maximal dosage of protein for maximal muscle protein synthesis is 2.2 g/kg
The minimal quantity of protein required to prevent deficiency and support normal functioning is around 0.8 grams per kg that you weigh.
For healthy individuals, the RDA is around 1 gram per kg, while for the elderly, the RDA is around 1.2 grams per kg.
The minimum required dosage for enhanced muscle protein synthesis is about 1.6 grams per kg of bodyweight.
To maximise muscle protein synthesis, a maximum dosage of 2.2 grams per kg spread out over four meals per day should be consumed. (Source)
An optimal amount of protein per meal is between 20 and 30 grams, split between 4-5 meals.
For a 70kg male, consuming 1.6 g/kg of protein would be 112 grams of protein per day. The optimal way to consume this would be by splitting the 112 grams by 4 meals over the course of a day, resulting in around 28 grams of protein per meal. (Source)
If the amount of protein per meal increased beyond 30 grams, adding an extra meal around 2-3 hours after the previous meal would be a better option.
Further Reading: The Optimal Protein Intake per Day for Muscle Building
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