Is Maximal Protein Absorption Per Sitting Thing?
If you’ve been lifting for long enough and making protein intake a priority you’ve probably heard a fellow gym enthusiast say something along the lines of “You shouldn’t have so much protein, your body can only absorb ‘X’ amount at a time”. I had heard this idea hammered home to the point of exhaustion years ago, so I decided to do some research of my own. Luckily, this concept is well researched and has some pretty definitive study results that will help to weed out the bro-science.
When you eat protein, your stomach uses its acid and enzymes to break it down into, amino acids.
These molecules are transported into the bloodstream by special cells that line the small intestine, and are then delivered to various parts of the body.
Your small intestine only has so many transporter cells, which limits the amount of amino acids that can be infused into your blood every hour, this is the basic framework for “protein absorption” (1).
Your body has many ways of slowing food passage through the small intestine as a way to buy time for nutrient absorption (2). It can even store amino acids in muscle for near-future needs. If there are still amino acids in the blood after doing all of the above, your body can convert them into glucose to fuel your brain and other cells (3). It’s also relevant to mention that many studies on intermittent fasting have found that eating the entire days’ worth of protein in a short window (followed by many hours of fasting) didn’t negatively impact muscle preservation (4, 5, 6, 7) which provides further evidence that protein absorption was not hindered by high levels of intake at once. I hope this helps some of you get your protein intake in worry free! <Sources in comments>