No more than 30-50 g of protein is absorbed in one meal. Can’t the body absorb more? This article will explain how protein is digested.
What is the maximum amount of protein per meal that the body can absorb? There is a hypothesis that a person assimilates 30-50 g of protein regardless of body weight (both men and women).
In fact, our body is capable of more.
Initial phases of protein digestion
Before we start arguing about numbers, let’s clarify exactly how protein is digested in the body.
The digestion process begins in the mouth, from where, after grinding, the food enters the esophagus. In the oral cavity, food, including protein, is thoroughly chewed and sent to the stomach, where the absorption of nutrients is already much faster.
Under the influence of gastric juice, consisting of hydrochloric acid, potassium chloride and sodium, protein denaturation occurs (chemical analysis and breakdown of food that has entered the stomach). Enzymes are produced that speed up the digestion process.
Pepsin is considered one of the key enzymes in protein digestion. It is believed that when protein is consumed in large quantities, the body needs additional inputs of this enzyme from the outside. But research on this subject continues, so it is too early to assert something reliably.
Final phases of protein digestion
After the protein is sufficiently cleaved by enzymes, the polypeptides extracted from it are sent to the duodenum – the vestibule of the small intestine. This is where most of the protein is digested and amino acids are absorbed. Digestive enzymes in the small intestine continue to break down polypeptides from isolated amino acids and some di- and tripeptides.
At the final stage of protein assimilation, isolated acids enter either the intestinal cells or the liver. Once in the liver, amino acids are finally used to maintain proper metabolism in accordance with the energy requirements of the body (for protein synthesis, as the basis for gluconeogenesis, etc.).
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So how much protein can the human body absorb in one meal?
With the basics of protein digestion in mind, let’s clarify how much protein our body can absorb in one meal. We ask how much protein the body can metabolize, but we don’t ask how well protein will be digested and utilized for muscle protein synthesis. The digestion and construction of muscle protein are different concepts.
The theory that our body is able to digest 30-50 g of protein does not stand up to biochemical or evolutionary criticism. The essence of this hypothesis is that our body cannot absorb more than 30-50 g of protein per meal, and therefore, the rest of the protein, eaten above the specified rate, simply flushes into the toilet.
In other words, instead of absorbing the excess of the supplied protein, our body magically bypasses the complex digestive process, which we wrote about above, and directs all the additional protein outside. Physiologically, if this were true, we would spend most of our lives on the toilet.
At the moment, research confirming that our body is not able to absorb more than 30-50 g of protein at a time is practically non-existent. The literature does confirm that the human body is capable of digesting a fairly large portion of protein, it just takes longer than digesting smaller portions.
This explains the fact that the body cannot quickly take in and redirect excess protein to the rectum. More protein is absorbed by reducing the rate of digestion in order to reduce the rate at which nutrients enter the small intestine. That is, when the stomach is full, the entire digestive tract is seriously slowed down.
For those wondering if the body is capable of absorbing 200 grams of protein at a time, the answer is yes. But, unfortunately, not all of the information received will be used for its intended purpose.
Protein can be stored in fat, but the biochemical reaction of this process is so ineffective that the result is hardly noticeable. Most likely, most of the protein that was not used for building muscles or other anabolic processes, after gluconeogenesis in the liver, is further stored in the body in the form of glycogen.
So you can eat a little more protein if you want at any time, just do not overdo it if you are concerned about the efficient use of amino acids from food.
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