title: Protein quality as determined by the Digestible Indispensable Amino Acid Score: evaluation of factors underlying the calculation.
abstract: The Food and Agriculture Organization of the United Nations recently recommended the adoption of a new and improved scoring system (Digestible Indispensable Amino Acid Score [DIAAS]) to quantify dietary protein quality. The DIAAS is based on the relative digestible content of the indispensable amino acids (IAAs) and the amino acid requirement pattern. Factors involved in calculation of the DIAAS include: use of the content and profile of IAAs as the basis for quality; methods for determination of the protein and amino acid content of the protein source; accuracy of individual requirement values for IAAs; normalization of IAA requirements by the estimated average requirement for protein; and basing the DIAAS on the true ileal digestibility of each IAA in the test protein. This review outlines the rationale for including each of these factors in the calculation of the DIAAS and describes associated potential errors.
authors.affiliation: R.R. Wolfe and I.-Y. Kim are with the Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. S.M. Rutherfurd and P.J. Moughan are with the Riddet Institute, Massey University, Palmerston North, New Zealand. rwolfe2@uams.edu.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Wolfe
authors.affiliation: R.R. Wolfe and I.-Y. Kim are with the Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. S.M. Rutherfurd and P.J. Moughan are with the Riddet Institute, Massey University, Palmerston North, New Zealand.
authors.forename: Shane M
authors.initials: SM
authors.lastname: Rutherfurd
authors.affiliation: R.R. Wolfe and I.-Y. Kim are with the Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. S.M. Rutherfurd and P.J. Moughan are with the Riddet Institute, Massey University, Palmerston North, New Zealand.
authors.forename: Il-Young
authors.initials: IY
authors.lastname: Kim
authors.affiliation: R.R. Wolfe and I.-Y. Kim are with the Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. S.M. Rutherfurd and P.J. Moughan are with the Riddet Institute, Massey University, Palmerston North, New Zealand.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Moughan
mesh_terms: D000601:Amino Acids, Essential / Q000032:analysis*; D000818:Animals; D004044:Dietary Proteins / Q000032:analysis*; D004063:Digestion; D023381:Endpoint Determination; D006801:Humans; D023421:Models, Animal; D008962:Models, Theoretical; D009751:Nutritional Requirements; D009753:Nutritive Value; D015203:Reproducibility of Results
chemical_list: D000601:Amino Acids, Essential; D004044:Dietary Proteins
keywords: essential amino acids; protein quality