FAO/INFOODS Guidelines for Converting Units, Denominators and Expressions Version 1.0 (2012)
Conversion of food data is done in the areas of nutrition (i.e. food composition and dietary assessment) and food safety (exposure assessment), and when reporting analytical data, including their publication in scientific articles. Food composition data are expressed in a variety of ways, depending on national conventions, practices of various institutions and journals requirements. However, to aggregate or compare data from diverse sources, it is often necessary to convert them.