Protein is one of the critical macronutrients required by the body for proper functioning, and is one of the key ingredients in functional foods bars and drink mixes. Protein supplements and functional foods are used for increasing muscle mass, as an aid to dieting, as meal replacements, and as a source of additional protein for vegetarians and others on restricted diets.  These products are particularly helpful for athletes, because extended workouts can result in catabolism, the use of muscle protein as fuel when muscle glycogen stores run low, and supplemental protein helps rebuild muscle protein stores.


The protein found in supplements and functional food bars may be sourced from whey, casein, egg albumin, soy or hemp. In addition, products can be formulated with a variety of amino acids, which are the building blocks of protein. The essential amino acids isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine all have critical roles to play in the body, and are often added singly or in groups to functional beverages and foods.