Dr. Berardi goes on to question that if you eat a meal containing 30g of protein and 95% of the protein is digested and absorbed through the intestinal mucosa, does that mean if you ate less protein, 100% would have been absorbed and if you ate more protein only 90% would be absorbed? Not at all, he claims. If you ate less protein, the time this protein sits in the GI tract would be shorter and fewer enzymes would be released so you'd probably digest and absorb 95%. And if you ate more protein, the time that this protein sits in the GI tract would be longer and more enzymes would be released so you'd probably digest and absorb about 95% of the protein.
All proteins are comprised of amino acids, and amino acids serve as the building blocks of proteins. Each protein, regardless of its source, is made up of approximately 20 amino acids. Since all proteins are comprised of the same 20 amino acids, how is one protein source different from another? The answer to this question is that the sequence of the amino acids differs from one type of protein to another. In addition, the composition of the amino acids that comprise a given protein is what makes one type of protein different from another. For example, soy does not have as much of the amino acid methionine as some other high-quality proteins, and egg protein has more branched chain amino acids than vegetable proteins.