How Much Protein Can Your Body Digest? Testing the 20-Gram Rule

When thinking about optimizing your protein consumption, how much is too much? We’ve established that protein is a vital dietary fuel for all kinds of reasons. But, at some point, does eating protein have no additional benefit and is eating more simply “overfilling” your tank?

The idea that your body has limits on how much protein you can digest is based on the concept of muscle protein synthesis or MPS. Muscle protein synthesis is your body’s natural way of breaking down protein and using it to help repair the muscles in your body. 

That’s because during exercise your body uses protein, something known as muscle protein breakdown (or MPB). The combination of muscle protein synthesis and muscle protein breakdown are important components of how you build muscle, and — more importantly for every exercise goal — how well you recover from exercise. 

And, some research has suggested that 20 grams of protein is the sweet-spot for maximizing muscle protein synthesis.

Which leaves you with a very important question: how much protein can your body digest, and — at some point — is more protein too much and not really adding any benefit?

In this episode of That’s Healthy, Right? host Adam Bornstein weighs the comparison of protein to the gas you put in your car, how to maximize your post-workout intake, and the science behind whether or not you should restrict how much protein you eat per serving.

Have a question you want to be considered for the show? To submit a question, email a voice recording that you can do here to

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How much protein can the body use in a single meal for muscle building? Implications for daily protein distribution — Journal of the International Society of Sports Nutrition 

Per Meal Dose and Frequency of Protein Consumption Is Associated With Lean Mass and Muscle Performance — Journal of Clinical Nutrition 

Is there a maximal anabolic response to protein intake within a meal? — Journal of Clinical Nutrition

Update on maximal anabolic response to dietary protein — Journal of Clinical Nutrition 

A high-protein diet for reducing body fat: mechanisms and possible caveats — Nutrition and Metabolism

Nutritional interventions to augment resistance training-induced skeletal muscle hypertrophy — Frontiers in Physiology  

Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis — The Journal of Physiology

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 — British Journal of Sports Medicine 

Effect of Protein Overfeeding on Energy Expenditure Measured in a Metabolic Chamber — American Journal of Clinical Nutrition 

Effect of different protein sources on satiation and short-term satiety when consumed as a starter — Nutrition Journal

Indicator Amino Acid–Derived Estimate of Dietary Protein Requirement for Male Bodybuilders on a Nontraining Day Is Several-Fold Greater than the Current Recommended Dietary Allowance — The Journal of Nutrition

What Will a Protein Shake Really Do to Your Body? – That’s Healthy, Right? Podcast

The Protein Guide: How Much Protein Do You Need? – Born Fitness

Our recommended protein: Ladder Whey Protein or Ladder Plant Protein [use code “Bornfitness30” for 30% off your entire purchase. No commission for us, just our way of saying thanks for listening]


Adam Bornstein: Is eating food to fuel your body the same thing as using gas to fuel your car? 

It’s an important thing to consider when talking about protein because many people believe that your body can’t handle or digest more than 20 grams of protein per serving.

And many of this is built on this idea that your body functions like a car, and that once your body, your fuel is on full, putting in extra fuel isn’t going to do anything. It’s just going to go to waste.

Now, the idea of 20 or even 30 grams of protein per serving is based on some pretty solid research focusing on muscle protein synthesis. MPS, or muscle protein synthesis, is your body’s ability to break down protein and use it to help your muscles grow and recover.

It is true that the research shows that there is a cap on MPS, and that cap can be stretched a little bit such as you might see an increase in the post-workout period. But let’s just assume, on average, that it’s true that you maximize muscle protein synthesis around 20 to 30 grams per serving.

Here’s the problem. Protein has many benefits that go far beyond muscle building and recovery. In fact, protein is the building block of every single cell in your body. Your hair, your skin, your nails, all depend on the amino acids that are in protein.

So, the idea that you need to restrict the amount of protein you eat just from a muscle-building outlook is overlooking all of the other benefits that protein has. 

Not to mention, protein is also more satiating so it’s going to leave you fuller. So, eating more can actually help you eat less overall calories per meal.

And, protein is the most metabolically active. About up to 30% of the calories you eat from protein will be burned during the digestion process.

For all of those reasons, there is no need to restrict yourself to only 20 or 30 grams of protein per serving because your body can most certainly handle it. 

And, there are a wide variety of health benefits that suggest eating a little bit more protein per meal might do your body well.