Early life is characterized by developmental milestones such as holding up the head, turning over, sitting up and walking that are typically achieved sequentially in specific time windows. Similarly, the early gut microbiome maturation can be characterized by specific temporal microorganism acquisition, colonization and selection with differential functional features over time. This orchestrated microbial sequence occurs from birth during the first years of age before the microbiome reaches an adult-like composition and function between 3 and 5 years of age. Increasingly, these different steps of microbiome development are recognized as crucial windows of opportunity for long term health, primarily linked to appropriate immune and metabolic development. For instance, microbiome disruptors such as preterm and Cesarean-section birth, malnutrition and antibiotic use are associated with increased risk to negatively affect long-term immune and metabolic health. Different age discriminant microbiome taxa and functionalities are used to describe age-appropriate microbiome development, and advanced modelling techniques enable an understanding and visualization of an optimal microbiome maturation trajectory. Specific microbiome features can be related to later health conditions, however, whether such features have a causal relationship is the topic of intense research. Early life nutrition is an important microbiome modulator, and ‘Mother Nature’ provides the model with breast milk as the sole source of nutrition for the early postnatal period, while dietary choices during the prenatal and weaning period are to a large extent guided by tradition and culture. Increasing evidence suggests prenatal maternal diet and infant and child nutrition impact the infant microbiome trajectory and immune competence development. The lack of a universal feeding reference for such phases represents a knowledge gap, but also a great opportunity to provide adequate nutritional guidance to maintain an age-appropriate microbiome for long term health. Here, we provide a narrative review and perspective on our current understanding of age-appropriate microbiome maturation, its relation to long term health and how nutrition shapes and influences this relationship.

Snacking is common in children and influenced by many factors. The aim of this study is to provide insight of both common and country-specific characteristics of snacking among 4–13 year old children. We analyzed snacking prevalence, energy and nutrient contributions from snacking across diverse cultures and regions, represented by Australia, China, Mexico, and the US using data from respective national surveys. We found that the highest prevalence of snacking was in Australia and the US (over 95%) where snacking provided one-third and one-quarter of total energy intake (TEI), respectively, followed by Mexico (76%, provided 15% TEI) and China (65%, provided 10% TEI). Compared to 4–8 year-olds, the consumption of fruits and milk was lower in 9–13 year-old children, with a trend of increasing savory snacks consumption in China, Mexico, and the US. The nutrient density index of added sugars and saturated fat was higher, especially in Australia, Mexico, and the US. Results suggested that snacking could be an occasion to promote fruit and vegetable consumption in all countries, especially for older children. Snacking guidelines should focus on reducing consumption of snacks high in saturated fat and added sugars for Australia, Mexico, and the US, whereas improving dairy consumption is important in China.

The aim of this study was to examine usual daily micronutrient intake of Chinese children based on data from the 2011 China Health and Nutrition Survey. We analyzed data from 4 to 17-year-old participants, who provided dietary data on three consecutive days combined with the household weighing method in 2011. Usual daily intake of each nutrient was estimated using a mixed effects model based on the China Food Composition published in 2009. The means, medians and percentages below Estimated Average Requirements (EAR) were reported for selected micronutrients, including calcium, sodium, potassium, iron, zinc, selenium, vitamin A, thiamine, riboflavin and vitamin C. For sodium and potassium, the means and the distribution of intakes were compared to the Adequate Intake (AI) level. The average usual daily intakes of all micronutrients increase with age, and the intakes of boys were found to be higher than girls in the same age group. The average calcium intake increased from 272 mg/day in 4–6 years to 391 mg/day in 14–17 years, but the percentage of inadequate calcium intake remained very high (>96%). The prevalence of inadequacy of calcium was the highest among the mineral nutrients reported in this study. As the requirements of micronutrients increased with age, the percentage of subjects with inadequate intake increased in the 11–17 years age groups. Among 14–17 years group, the percentages of study participants with dietary intakes of calcium, iron, zinc, selenium, vitamin A, thiamine, riboflavin and vitamin C below the EAR were 96.8%, 18.8%, 37.6%, 72.8%, 36.8%, 91.8%. 85.9% and 75.5%, respectively. Among 11–13 years group, the percentages of study participants with dietary intakes of iron, zinc and vitamin A below the EAR were 23.5%, 41.5%, and 41.6%, respectively. Thus, micronutrient deficiency is a problem in Chinese children. Nutrition education and intervention programs are needed to address these nutritional gaps.

Evaluate foods and beverages consumed, and energy and nutrient densities that constitute morning, afternoon, and evening snacking periods among children in the US. Evaluate snacking behavior using the National Health and Nutrition Examination Survey, 2009-2012. Children aged 4-8 and 9-13 years (n = 3,647). Self-reported foods and beverages reported as snacks were aggregated into morning (0:00-12:00 hours), afternoon (12:00-18:00 hours), and evening (18:00-24:00 hour) snacking periods. Intakes and amounts consumed during different snacking periods were analyzed from per capita weighted averages using SAS 9.2 and SUDAAN software. Statistical differences were detected using Student t test for means and chi-square test for prevalence data. Snacking contributed 25% of daily energy in both age groups, with the morning snacking period contributing the least energy. The most frequently consumed food groups across all snacking periods were water, snacks and sweets, nonalcoholic beverages, milk and dairy, and fruit. Nutrient densities varied among different snacking periods; the morning snack period for 4- to 8-year-olds was the most nutrient dense. Snacking is an important contributor to energy and nutrients in children's diets, but foods and beverages selected vary by time of day and age. Modifying snacking choices, especially in the afternoon, could improve the nutritional quality of children's diets.

Objective: Excessive energy intake and poor food choices are major health concerns associated with overweight and obesity risk. This study aims to explore disparities in energy intake and the contributions from fat and animal source foods among Chinese school-aged children and adolescents in different communities based on urbanization levels. Design: Three consecutive 24 h recalls were used to assess dietary intake. Subjects’ height and weight were measured using standard equipment. Standardized questionnaires were used to collect household demographic and socioeconomic characteristics by trained interviewers. Setting: The 2011 China Health and Nutrition Survey is part of an ongoing longitudinal household survey across 228 communities in nine provinces and three mega-cities in China. Subjects consisted of children aged 4–17 years (n = 1866; 968 boys and 898 girls). Results: The estimated average energy intake was 1604 kcal/day (1706 kcal/day for boys and 1493 kcal/day for girls). Proportions of energy from fat and animal source foods were 36.8% and 19.8% respectively and did not differ by gender. Total energy intake showed no significant disparity, but the proportion of energy from fat and animal source foods increased with increasing urbanization levels and increasing household income level. The largest difference in consumption percentages between children in rural areas and those in highly urban areas was for milk and dairy products (14.8% versus 74.4%) and the smallest difference was seen in percent consuming meat and meat products (83.1% versus 97.1%). Conclusions: Results of this study highlight the need for developing and implementing community-specific strategies to improve Chinese children’s diet quality.

Eating habits of lactating women can influence the nutrient composition of human milk, which in turn influences nutrient intake of breastfed infants. The aim of the present study was to identify food patterns and nutritional adequacy among lactating women in Europe. Data from a multicentre European longitudinal cohort (ATLAS study) were analysed to identify dietary patterns using cluster analysis. Dietary information from 180 lactating women was obtained using 3-d food diaries over the first 4 months of lactation. Four dietary patterns were identified: ‘vege-oils’, ‘fish-poultry’, ‘confectionery-salads’ and ‘mixed dishes’. Nutrition adequacy was not significantly different between clusters, but the ‘vege-oils’ cluster tended to yield the highest nutrition adequacy measured by Mean Adequacy Ratio. Compared with European dietary reference values (DRVs) for lactating women, women in all clusters had inadequate intakes of energy, pantothenic acid, folate, vitamin C, vitamin A, vitamin D, zinc, iodine, potassium and linoleic acid. Adequate intake for fibre and α-linolenic acid was only achieved in the ‘vege-oils’ cluster. Overall, fat intake was above DRVs. The present study showed that various dietary patterns do not adequately supply all nutrients, indicating a need to promote overall healthy dietary habits for European lactating women.