wastes being excreted by urine; needs are increased for growth, illness, injury etc. ??? ??? ??? amino acids building blocks of all proteins; 20 common which are all needed; body can only make 11 of them ??? ??? ??? recommended intake of proteins 10-35% of daily calories ??? ??? ??? low protein foods whole grains, fruit, thin-sliced meat, oils such as olive and flaxseed ??? ??? ??? classes of amin