Episode 25 – How Much Protein Can the Body Absorb in a Single Meal?

Key Topics Covered

  • The difference between “total protein absorbed” and “total protein used for muscle building”
  • The evidence behind the general recommendations of 25g every 1.5-2 hour
  • Our protein recommendations for optimal muscle growth

Google says – “The most your body can absorb in one sitting is around 25g of protein. In this case, “one sitting” refers to the time over the course of 1.5-2 hours.”

How Studies Measure This

  • Studies will often measure the acute spike in muscle protein synthesis after consuming protein.
  • It’s usually measured by having an individual consume 10, 20, 30 then 40g of protein. They’ll see how much muscle protein synthesis rises by. Once it stops rising significantly, that is deemed the optimal amount of protein.
  • Another study looked at elderly people post full-body workout. They found that 70g was the maximum amount that was able to be used for muscle growth.
  • It’s size dependant. Typically, people who are larger will require more and vise versa.

Why This Doesn’t Make Sense

There’s a difference between “absorbed” and “used for muscle building”.

  • The amount of protein you absorb in a meal is not dictated by how much protein is in that meal.
  • Pretty much all protein will be absorbed and used to some capacity. 
  • Because protein has multiple functions inside the body.
    • Eg. Converted to glucose and used as energy.
  • Protein digestibility (how much is absorbed) differs between protein sources but is not affected by how much protein there is in one sitting.
    • Eg. Legumes vs steak
  • Research highlights that 1.6-2.2g/kg of protein per day outperforms lower amounts.  
    • Eg. If someone weighed 80kg and aimed for 130g of protein (bottom of that spectrum). If they ate 4 meals that had 25g protein since that is the MAX (according to google) that could be absorbed they would still only get 100g protein. They would fall short of their target by 30g.  
  • Based on the above, it is practically impossible for BOTH the total protein target goal AND the theoretical maximum absorption amount described to coexist. 

What Does Make Sense

  • Total protein intake far outweighs timing.
  • In terms of muscle growth, reaching that 1.6-2.2g/kg of protein per day is far more important than consuming the 0.4-0.6g/kg of protein every 2-3 hours.
  • Timing still matters.

Protein Requirements, In Order of Priorities for OPTIMAL Muscle Growth

  1. Total protein intake – If you’re lean, aim for the higher end of 1.6-2.2g/kg of protein per day and vise versa.
  2. Timing – 0.44-0.5g/kg/meal, 4-6 times per day.
    • In saying that, the study showed that 3 meals is almost as good as 4.
    • 4-6 meals is important for hitting the leucine threshold though. Once you go above 6 you’re less likely to hit the threshold.
optimising protein intake for athletes
protein prioritisation pyramid

Overall, focus on total daily protein intake and spreading it throughout the 4-6 meals per day. Don’t worry about going over the “upper limit” of protein per meal.

Relevant Resources/ Links

Studies Mentioned

Useful Blog Posts