# Incomplete protein

> Protein lacking some essential amino acids. Since most protein-containing foods we eat are complete proteins, the complete/incomplete distinction is not particularly meaningful.

<Protein> lacking some <essential amino acids>. Since most protein-containing foods we eat are complete proteins, the complete/incomplete distinction is not particularly meaningful.

The sole exception is <gelatin>, an <animal protein>. Gelatin completely lacks the essential amino acid <tryptophan>.