About 40 years ago I had to be hospitalized after a bad bout with asthma. During my stay in the hospital, I had a discussion with a young pharmacy intern (it was a teaching hospital) about sports nutrition, which was then as now one of my favorite topics of discussion. When we got on the subject of protein needs for bodybuilding, the pharmacy student said that no one can absorb more than 30 grams of protein in a single meal. This wasn't the first time I had heard that statement. The notion that 30 grams of protein represented the maximal amount of protein that can be absorbed was common knowledge among bodybuilders and athletes, despite the fact that no one seemed able to pinpoint the precise origin of the statement. I had heard it so often that I attempted to find where this admonition about protein came from. I checked various nutrition-related medical journals and nutritional as well as biochemical textbooks, but it was nowhere to be found. I came to the conclusion based on my inability to find the source of the 30-gram rule that it was simply made up and passed along to the point where it somehow became an established fact. As such, when the pharmacy intern once again declared that ingesting any more than 30 grams of protein was a waste, I felt compelled to challenge his assertion. I did this by offering to make a bet that he could not produce any evidence at all to prove the 30-gram limit was real. When I questioned him as to his source for the 30-gram rule, he could not supply any source. As such, he seemed to have found this out the same way that I did--from other people stating it as an accepted fact. I made the wager for $10,000, which would have been disastrous had I lost the bet since I didn't have that much money available at the time.
It turns out that I never saw the pharmacy intern again. But I think I would have won that bet since I'm confident that back then, the limits of protein uptake in any meal were not established. Instead, general rules about protein intake prevailed, such as you should eat a large variety of protein foods from animal sources, such as that derived from milk, meat, eggs, fish, and poultry. Bodybuilders knew that you needed to ingest a higher protein diet to gain muscle, and it was thought that you absorbed and used all the protein you ingested for that purposeInterestingly, back then scientists said that bodybuilders didn't need to ingest any more protein than a person who did not exercise at all. This made no sense and still doesn't today since many vegan advocates are still making the same statement: athletes and people engaged in exercise don't need to ingest any more protein than the average sedentary . . .