Research Approaches and Methods for Evaluating the Protein Quality of Human Foods Proposed by an FAO Expert Working Group in 2014.

The Protein Digestibility Corrected Amino Acid Score (PDCAAS) has been adopted for assessing protein quality in human foods since 1991, and the shortcomings of using the PDCAAS have been recognized since its adoption. The 2011 FAO Expert Consultation recognized that the Digestible Indispensable Amino Acid Score (DIAAS) was superior to the PDCAAS for determining protein quality. However, there were insufficient human data on amino acid digestibility before adopting the DIAAS. More human data were needed before DIAAS could be implemented. In 2014, FAO convened an expert working group to propose and agree on research protocols using both human-based assays and animal models to study ileal amino acid digestibility (metabolic availability) of human foods. The working group identified 5 research protocols for further research and development. A robust database of protein digestibility of foods commonly consumed worldwide, including those consumed in low-income countries, is needed for an informed decision on adopting the DIAAS. A review on the impacts of using the DIAAS on public health policies is necessary. It would be advantageous to have a global coordinating effort to advance research and data collection. Collaboration with international and national agriculture institutes is desirable. Opportunities should be provided for young researchers, particularly those from developing countries, to engage in protein-quality research for sustainable implementation of DIAAS. To conclude, the DIAAS is a conceptually preferable method compared with the PDCAAS for protein and amino acid quality evaluation. However, the complete value of the DIAAS and its impact on public health nutrition cannot be realized until there are sufficient accumulated ileal amino acid digestibility data on human foods that are consumed in different nutritional and environmental conditions, measured by competent authorities. A future meeting may be needed to evaluate the size and quality of the data set and to determine the timeline for full adoption and implementation of the DIAAS.

The adult male equivalent concept and its application to Household Consumption and Expenditures Surveys (HCES).

BACKGROUND: Knowledge of the amount and quality of food consumed by a population is essential in determining the adequacy of the food availability and supply. Since its founding the Food and Agriculture Organization (FAO) has developed methods for determining food availability and consumption that may be useful to other investigators. OBJECTIVE: Based on FAO's 60 years of experience in conducting Household Consumption and Expenditures Surveys (HCES), to explain and demonstrate the advantages and use of the Adult Male Equivalent (AME) and Equivalent Nutrition Unit (ENU) concepts. METHODS: The important factors related to the AME and ENU, such as energy requirements, size and composition of the food consumer unit, and attendance at meals, are explained through the examples of two hypothetical families: a family consisting of a father, a mother, a 12-year old daughter, and a 3-year old son plus an adult guest; and a family consisting of a single mother, a 10-year old son, and two daughters, 6 and 4 years of age. The reader is guided through the steps in calculating the AME and ENU. RESULTS: The various scenarios of the composition, size, and attendance at meals of the consumer unit show that the calculated food energy adequacy can range from +2% to -29%. CONCLUSIONS: Care and attention must be given to correctly attributing the consumers of the food intake measured or estimated. In addition, use of these concepts allows for a valid comparison of food consumption units of various sizes and compositions.