Interactions between environmental factors and predisposing genes could be involved in the development of coeliac disease (CD). This study has assessed whether milk-feeding type and HLA-genotype influence the intestinal microbiota composition of infants with a family history of CD. The study included 164 healthy newborns, with at least one first-degree relative with CD, classified according to their HLA-DQ genotype by PCR-SSP DQB1 and DQA1 typing. Faecal microbiota was analysed by quantitative PCR at 7 days, and at 1 and 4 months of age. Significant interactions between milk-feeding type and HLA-DQ genotype on bacterial numbers were not detected by applying a linear mixed-model analysis for repeated measures. In the whole population, breast-feeding promoted colonization of C. leptum group, B. longum and B. breve, while formula-feeding promoted that of Bacteroides fragilis group, C. coccoides-E. rectale group, E. coli and B. lactis. Moreover, increased numbers of B. fragilis group and Staphylococcus spp., and reduced numbers of Bifidobacterium spp. and B. longum were detected in infants with increased genetic risk of developing CD. Analyses within subgroups of either breast-fed or formula-fed infants indicated that in both cases increased risk of CD was associated with lower numbers of B. longum and/or Bifidobacterium spp. In addition, in breast-fed infants the increased genetic risk of developing CD was associated with increased C. leptum group numbers, while in formula-fed infants it was associated with increased Staphylococcus and B. fragilis group numbers. Overall, milk-feeding type in conjunction with HLA-DQ genotype play a role in establishing infants' gut microbiota; moreover, breast-feeding reduced the genotype-related differences in microbiota composition, which could partly explain the protective role attributed to breast milk in this disorder.

Background: Although adequacy of nutrient intake has been studied considerably in children and adolescents across Europe, the factors associated with nutritional risk have rarely been addressed. This study was developed in order to explore the nutritional intakes of Spanish children and the factors influencing the risk of nutritional inadequacy. Objectives: To evaluate socio-economic and lifestyle variables associated with nutritional adequacy in Spanish children and adolescents. Methods: A cross-sectional study utilising face-to-face interviews. A random sample of 3,534 individuals aged 2–24 years were interviewed by a team of 43 dieticians in the subjects’ homes. Interviews included two 24-hour recalls (a second 24-hour recall in 25% of the sample) and other questions, including lifestyle. Weight and height were measured in all subjects. Under-reporters (18%) were excluded from the present analysis. An unconditional logistic regression analysis was used to identify variables associated with greater nutritional risk. Results: The participation rate was 68%. Twenty percent of males and 50% of females were classified as being at high nutritional risk. Variables associated with increased nutritional risk were: age between 14 and 24 years, being female, low social class, low educational level of the mother, having more than one sibling, smoking, watching TV during meals, sedentary habits at leisure time, infrequent meals and a poor quality breakfast. One dietary factor closely associated with nutritional risk was a failure to consume ready-to-eat cereals. Conclusions: Nutritional risk during infancy and adolescence is associated with socio-economic and educational variables of the family, and some lifestyle factors including physical activity and the quality of the breakfast meal.

A systematic literature search identified studies validating the methodology used for measuring the usual dietary intake in infants, children and adolescents. The quality of each validation study selected was assessed using a European micronutrient Recommendations Aligned-developed scoring system. The validation studies were categorised according to whether the study used a reference method that reflected short-term intake ( < 7 d), long-term intake ( ≥ 7 d) or used biomarkers. A correlation coefficient for each nutrient was calculated from the mean of the correlation coefficients from each study weighted by the quality of the study. Thirty-two articles were included in the present review: validation studies from infants (1–23 months); child preschool (2–5 years); children (6–12 years); adolescents (13–18 years). Validation of FFQ studies in infants and preschool children using a reference method that reflected short-term intake showed good correlations for niacin, thiamin, vitamins B₆, D, C, E, riboflavin, Ca, K, Mg, Fe and Zn (with correlations ranging from 0·55 for vitamin E to 0·69 for niacin).Regarding the reference method reflecting short-term intake in children and adolescents, good correlations were seen only for vitamin C (r0·61) and Ca (r0·51). Using serum levels of micronutrient demonstrated that the 3 d weighed dietary records was superior to the FFQ as a tool to validate micronutrient intakes. Including supplement users generally improved the correlations between micronutrient intakes estimated by any of the dietary intake methods and respective biochemical indices.