The authors discuss problems associated with the use of the energy adequacy ratio as an indicator of nutritional status in population-based studies derived from household food consumption surveys. They describe the use of food consumption data to estimate family energy intake and to compare it among families and with family requirements to determine the family energy adequacy ratio. The article also discusses the use of international recommendations for human energy requirements and their limitations, based on the lack of consideration of non-food conditions, adaptive mechanisms, inadequacy of estimates of the baseline metabolism rate, and the lack of information to evaluate energy expenditure in non-work physical activities in the household surveys consulted. To illustrate the discussion, the authors use data from the National Family Budget Survey (ENDEF) conducted by the Brazilian Census and Statistics Bureau (IBGE) in 1974-1975. The article concludes that the main use of the adequacy ratio is to identify families suffering food restriction.