Current Concepts concerning Indispensable Amino Acid Needs in Adults and Their Implications for International Nutrition Planning

Abstract

Using a newly proposed amino acid scoring pattern, an assessment is made of the capacity of diets in developed and developing countries to satisfy human amino acid needs. The new adult pattern differs from that proposed by FAO/WHO/UNU (1985) for the adult but is similar to that for two- to five-year-old children. FAO food availability data were used to evaluate the dietary patterns in selected countries, including those of Africa, the Far East, and the Near East. Lysine appears to be the limiting amino acid in diets heavily dependent on cereals, characteristic of those in poor countries; the analysis reveals that for these countries the mean lysine supply is below the newly estimated requirements, implying that adults could be at risk of an inadequate intake, especially when total protein availability is low. Further, this analysis reveals that when animal foods contribute about one-third of the total protein supply or when animal foods together with pulses and soybeans account for about 40% of the total protein supply, the lysine requirement for the population will be met. For the US diet, the high proportion of the total protein contributed by animal foods, about 68%, provides a lysine intake that is well above the estimated requirement and that is almost constant across all age and sex groups. This reassessment leads to the recommendation that, especially in countries whose diet is mainly dependent on cereals, complementation to improve dietary protein quality should remain a consideration in the design and implementation of food, nutrition, and agricultural programmes and policies.