A balance between supply and demand of animal protein in Chile and particularly of the essential amino acid lysine was the main objective of this study. A preliminary study was conducted to determine human requirements of protein and essential amino acids for the Chilean population. Protein and lysine requirements were met according to official data for Chile. A more thorough investigation was carried out to determine the availability of animal protein among different social economic status (quintiles). Animal protein availability in the lowest income quintile does not cover the protein and lysine requirements according to data from the V Survey of Income and Expenses (1997). The second quintile closely satisfies the requirements and therefore, are in a state of nutritional vulnerability. Finally, the minimal recommended quantity of protein for any healthy individual must come from animal sources in at least 50%. Such a recommendation is based upon the better digestibility of animal proteins and because they contribute with almost all the nutritional needs for essential amino acids.