Estimation of the energy needs at the national level: use of the FAO/WHO/UNU 1985 approach

This paper analyzes the methodology proposed by FAO/WHO/UNU 1985 to determine energy requirements and recommendations for population groups. The physiological basis for individual requirements and the components to estimate the energy expenditure of population groups, are presented. This new approach requires a detailed knowledge of the distribution of the population by sex, age and level of physical activity. In the absence of physical activity data the distribution by employment category may be used. Our study suggests characterizing the population through the use of biotypes, according to sex, age and level of physical activity. This new approach also requires the knowledge of weight and height of a representative sample of the population. The planner should also consider a desirable level of physical activity for the population, and decide if the energy recommendation should optimize the weight and height of individuals to promote improved physical well being and health status. The application of this approach to a specific country in Latin America revealed that the available data are insufficient for an adequate estimation of energy needs of the population. Nevertheless, results suggest that the energy gaps for urban sedentary groups are less than those calculated using the traditional FAO/WHO 1973 reference pattern. The energy needs of the countries in the Region will increase as the infant population improves physical development more in accordance with the full expression of their genetic endowment. Further increases in energy needs are estimated as the general population increases the level of discretionary physical activity.