"Protein intake"

It's said that our bodies only can consume/utilize 30grams of protein per serving.

I find this to be redundant.

Your body adjusts to whatever you do or don't do to it. You are the driver of the wheel for the vehicle that is your body. If you want to put on mass/gain muscle,you can train your body to absorb an extensive amount of protein. Give it about 2 weeks(same as anything else concerning your body),and watch the results. If you wanted to be in a deficit or slim down,for about 2 weeks consistently lower your protein intake and watch the difference. As far as muscle,protein is a major source of development for that.