It is true that protein is made up of amino acids. But not all protein sources or amino acids they contain are equal. There are 9 essential amino acids and 11 are non-essential (or conditional). Essential amino acids need to be in our diet. The unique blend of essential amino acids in Rejuvenate has been developed over 17 years of research and 25 published peer reviewed clinical trials by some of the world's top researchers in protein, amino acids and muscle metabolism. It is patented and clinically proven to be more effective that protein alone in preserving muscle as you age and helping to prevent muscle loss as you age.