All bodybuilders have experienced protein gas and other side effects, when we first started a high protein diet. Protein is harder to digest than carbohydrates. Many bodybuilders believe in a certain amount the body can only digest in a given meal. The standard numbers that gets thrown around, is usually 30 or 50 grams. This is why bodybuilders break up their meals into roughly 6 a day. This allows a steady supply of aminos throughout the day, while minimizing protein waste and side effects from excess protein.
The idea of 30 to 50 grams comes from some obscure scientific studies. Most of the studies are done on sedentary individuals with no protein diet experience. I wouldn’t find any studies convincing, unless it was done on experienced bodybuilders(or athletes) on a high protein diet before the study. Our protein digestion, will depend on our genetics, and diet and training experience.
A person just starting a high protein diet won’t be able to digest very much protein. After a few weeks, the side effects will get much better with the same high protein diet. This is because their body has adapted, by increasing stomach enzymes to break it down easier. Everytime you increase your calories and protein intake, your body will adapt a little more. In other words, just like training, your body will adapt it’s digestion to what you eat. Everybodies genetics will be different too. How much you can digest will also depend on your sex. Not everyone will digest protein at the same level naturally.
I believe that a 3rd factor could be weight training. Excercise probably causes physiological changes in the digestion, as the body will demand protein to heal muscles. So unless a study is done on someone who is an active athlete, who has been on a high protein diet for many weeks or months, the study won’t mean much. Even if we could pinpoint the number as said earlier, there still will be differences in each individual due to genetics and their sex.
How can we tell if we aren’t digesting it all?
If you notice side effects, but you haven’t recently increased your protein intake, then it’s too high per meal. Side effects of your protein not digesting properly could include; very bad gas, diarrhea, or nausea.
What can I do to help protein digestion?
You could take a protein digestion enzymes bromelain with each meal meal, or break up the protein into less amounts into more meals.