To assess Fe intake, calculate the prevalence of inadequate Fe intake and identify food contributors to Fe intake during 2003 and 2008 in a population-based study, reflecting before and after the mandatory fortification of flour with Fe.

Two cross-sectional population-based studies conducted in 2003 and 2008. Dietary intake was evaluated by 24 h recall and the Software for Intake Distribution Estimation (PC-SIDE) was used to estimate within-person variance and prevalence of inadequate Fe intake. The statistical analysis was conducted considering the complex survey design.

São Paulo, Brazil.

Adolescents, adults and elderly adults of both sexes, interviewed in 2003 (n 2386) and 2008 (n 1661).

The Fe intake mean increased in all populations in the post-fortification period. A reduction of over 90 % was observed in the prevalence of inadequate Fe intake among men for all age groups analysed. When evaluating women, despite the substantial reduction (over 63 %), prevalence of inadequate Fe intake remained high (34 %) in those aged 19–50 years. Major food contributors to Fe intake before fortification were beans, beef, vegetables and dairy. There was an alteration in the contributors in the post-fortification period, with bread, beef, beans and biscuits as main contributors.

The mandatory fortification with Fe significantly furthered the reduction in the prevalence of inadequacy, except among women of reproductive age, and changed the main contributors to this nutrient in the studied population. Therefore, monitoring of Fe addition in flour is essential to assess compliance to the fortified flour policy and to guarantee a safe Fe intake for all the population.

To verify associations of income and education with nutrient intakes in Brazilian adults.

Data from the population-based National Dietary Survey conducted in 2008–2009. Family per capita income and education levels were categorized into quartiles. Prevalences of inadequate nutrient intakes and excessive intakes of saturated fat and Na were calculated by using the method prescribed by the National Cancer Institute. The Estimated Average Requirement was used as a reference for micronutrient intake. Linear regression models for both the independent and the mutually adjusted associations of education and income with nutrient intakes were tested. Interaction between education and income was tested.

Households (n 13 569) selected using a two-stage cluster sampling design.

Food records for two non-consecutive days were obtained for 21 003 Brazilian adults (aged 20–59 years).

For most of eleven nutrients, the prevalence of inadequate intake declined with increasing income and education levels; however, it remained high across all income and education quartiles. Excessive intake of saturated fat and low fibre intake increased with both variables. Most nutrients were independently associated with income and education in both sexes. Fe, vitamin B12 and Na intakes among women were associated only with education. There was an interaction between income and education for Na intake in men, P intake in women and Ca intake in both sexes.

Education is one important step to improve nutrient intakes in Brazil. Emphasis should be laid on enhancing dietary knowledge and formulating economic strategies that would allow lower-income individuals to adopt a healthy diet.

To estimate the prevalence of inadequate nutrient intake among adolescents and the association between socio-economic variables and nutritional status.

Cross-sectional study with a population-based sample.

The usual nutrient intake distribution was estimated using the Iowa State University method. The Estimated Average Requirement cut-off point method was used to determine the proportion of adolescents with inadequate intake for each nutrient, according to sex, income, parental educational level and nutritional status.

Twenty-four-hour dietary recalls were applied in 525 male and female Brazilian adolescents aged 14–18 years.

The highest prevalence of inadequate nutrient intake was observed for vitamin E (99 % in both sexes). For male and female adolescents, the prevalence of inadequate intake was: Mg, 89 % and 84 %; vitamin A, 78 % and 71 %; vitamin C, 79 % and 53 %; and vitamin B6, 21 % and 33 %, respectively. The prevalence of inadequate intake for niacin, thiamin, riboflavin, Se, Cu and vitamin B12 was <15 %. Individuals in the lower income and lower parental educational level strata had the highest risk of having inadequate intake for P, riboflavin and vitamins A, B6 and B12. Compared with non-overweight individuals, overweight individuals had a higher risk of inadequate intake for Mg, vitamin A, P, thiamin and riboflavin.

The present study found a high prevalence of inadequate intake of nutrients that are recognised as being protective against chronic diseases. Adolescents in the lower income and lower parental educational level strata were less likely to have their nutrient intake requirements met.

To summarise the applications and appropriate use of Dietary Reference Intakes (DRIs) as guidance for nutrition and health research professionals in the dietary assessment of groups and individuals.

Key points from the Institute of Medicine report, Dietary Reference Intakes: Applications in Dietary Assessment, are summarised in this paper. The different approaches for using DRIs to evaluate the intakes of groups vs. the intakes of individuals are highlighted.

Each of the new DRIs is defined and its role in the dietary assessment of groups and individuals is described. Two methods of group assessment and a new method for quantitative assessment of individuals are described. Illustrations are provided on appropriate use of the Estimated Average Requirement (EAR), the Adequate Intake (AI) and the Tolerable Upper Intake Level (UL) in dietary assessment.

Dietary assessment of groups or individuals must be based on estimates of usual (long-term) intake. The EAR is the appropriate DRI to use in assessing groups and individuals. The AI is of limited value in assessing nutrient adequacy, and cannot be used to assess the prevalence of inadequacy. The UL is the appropriate DRI to use in assessing the proportion of a group at risk of adverse health effects. It is inappropriate to use the Recommended Dietary Allowance (RDA) or a group mean intake to assess the nutrient adequacy of groups.