The aim of this study was to apply methodological procedures to determine the prevalence of adequacy of Iron and vitamin C in children's diets. It was included 238 children aged 2 to 3 years enrolled in 2009 in 25 day care centers in the municipality of Rio de Janeiro. Dietary intake was assessed by weighing the food and food record. Assessing the prevalence of nutrient adequacy took into consideration the individual and the group. The best estimate of the needs of the individual is given by the estimated average requirement (EAR), since we do not know the true needs of the individual who is being evaluated. To estimate the need of the group method was used EAR as the cutoff. The prevalence of adequacy of iron and vitamin C in children's diets was 91.2 and 62.2%, respectively. All necessary to achieve the method EAR as the cutoff were used, but became unviable the adjustment of the observed consumption data to estimate the distribution of usual intake in this group. We conclude that the study of probability of adequacy of habitual diet in iron and vitamin C in the age group in question was only possible with the use of procedures for the individual.