Since 1949, FAO has convened groups of experts to evaluate current scientific knowledge in order to define the energy requirements of humans and propose dietary energy recommendations for populations. The World Health Organization (WHO) joined this initiative in the early 1950s, and the United Nations University (UNU) in 1981. New scientific knowledge generated in the 20 years since the last consultation was held prompted the assembly of a new expert consultation to make recommendations for energy requirements of populations throughout the life cycle. This publication is the report of that consultation, which took place from 17 to 24 October 2001 at FAO headquarters in Rome. The report is not meant merely to describe the energy expenditure and requirements of population groups. It is intended also to be prescriptive in supporting and maintaining health and good nutrition, defining human energy requirements and proposing dietary energy recommendations for populations.
The new concepts and recommendations set forth in the report include: calculation of energy requirements for all ages; modification of the requirements and dietary energy recommendations for infants, older children and adolescents; proposals for different requirements for populations with lifestyles that involve different levels of habitual physical activity; reassessment of energy requirements for adults, based on energy expenditure estimates expressed as multiples of basal metabolic rates; classification and recommendations of physical activity levels; an experimental approach for factorial estimates of the energy needs of pregnancy and lactation; and recommendations for additional dietary energy needs in the two last trimesters of pregnancy. The report is accompanied by a CD-ROM software program and instruction manual on calculating population energy requirements and food needs.