Derivation of Nutrient Values for FAO Statistical Databases

The FAO Food Balance Sheets include 445 food items, some of which are summarizations of many foods, for 188 countries. The energy, protein, fat and refuse values used for calculating the nutrient supplies are presently being completely revised and the coverage of nutrients is being enlarged by including selected minerals (calcium and iron) and selected vitamins (retinol, beta carotene equivalent, thiamin, riboflavin, niacin and ascorbic acid). A great number of country and regional food composition tables are being reviewed for this purpose. While in theory it seems straightforward to derive the data from the food composition tables, in practice many problems, doubts and difficulties arise due to a number of reasons: non-standardization of description/nomenclature of foods in food composition tables and of methods of analysis or calculation of nutrients and energy. The main intent of the paper is to analyze and illustrate this aspect of the food balance sheets—that is applying food composition data. A variety of cases are examined and presented and some practical examples given. The knowledge of the situation and the identification of the reasons which determine it, can contribute to an improved preparation, interchange and comparability of food composition data on international basis.