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Optimal growth is a central theme in human nutrition. Growth is a proxy indicator of health and well-being. Adequate food intake is crucial for growth. Nurturing a healthy generation of children is a social imperative. This formed the title of the workshop. Much remains to be learned on the factors that limit and enhance food intake in children. Hence, the workshop focused on research gaps and opportunities. The workshop covered 3 sessions that involved an excellent array of presentations. The first session was entitled “Early Eating Behavior and Taste Development Influence in Children.”

According to the World Health Organization (WHO), the global number of children aged from 0 to 5 years with overweight or obesity has increased from 32 million in 1990 to 41 million in 2016. This trend concerns most countries around the globe, although we may see obesity rates stabilizing in some countries, such as in northwestern Europe [NCD Risk Factor Collaboration: Lancet 2017; 390: 2627–2642]. Obesity is associated with comorbidities, placing children at a greater risk of developing type 2 diabetes, cardiovascular disease, and even psychological disorders such as low self-esteem. In this context, the WHO has developed a framework to prioritize 6 actions that could help put an end to childhood obesity [Commission on Ending Childhood Obesity: Report of the Commission on Ending Childhood Obesity, 2016]. The importance of nutrition for children is present in 3 of these actions, which relate to the content of this workshop: (1) the promotion of healthy food intake, (2) early childhood diet and physical activity, and (3) health, nutrition, and physical activity for schoolage children. In this context, it is more topical than ever to ensure children receive the best nutrition from the start of life, and even before, and develop healthy eating habits which could be maintained throughout life. In relation to these issues, in the first session of the workshop entitled Nurturing a Healthy Generation of Children: Research Gaps and Opportunities , the development of eating behaviors in the early years of life has been addressed from the very early months of postnatal life according to several themes related to modifiable factors: the role of sensory inputs, the role of dietary experience, and the effect of parental feeding practices.

Sophie Nicklaus et al. focused on the development of taste and flavor preferences and its consequences on children’s eating behaviors. After birth, when foods are orally exposed, infants discover the intrinsic properties of foods, with a variety of tastes, flavors, textures, as well as energy densities. Here, the focus was on deciphering the involvement of taste and olfaction in the early establishment of eating behavior based on data collected in the OPALINE birth cohort (Observatory of Food Preferences in Infants and Children), which was followed up in the area of Dijon (France). Taste and flavor preferences were studied in those children in relation to food acceptance over the first 2 years of life. The data show that both taste and flavor preferences evolve during this period: for instance, saltiness acceptance increased sharply between 3 and 12 months, while rejection of unpleasant food odors developed between 8 and 22 months. At the beginning of the complementary feeding period, a higher preference for some basic tastes (sweet, sour, and umami tastes) was associated with a higher acceptance of foods with similar tastes (sweet, sour, and umami, respectively); and, similarly, rejection of the odor of trimethylamine and dimethyl disulfide were related to the rejection of fish and sulfurous cheeses, respectively. Further in development, at 20 months, food neophobia was associated with flavor differential reactivity (within-subject variability across flavors) but not to taste differential reactivity (within-subject variability across tastes), underlying the importance of olfaction in the development of neophobic reactions. Altogether, these data highlighted the sensitivity of infants and toddlers to the sensory inputs from foods, which also contribute to the pleasure of eating.

Andrea Maier-Nöth highlighted some mechanisms by which infants and toddlers learn to like vegetables, which is a critical issue given that children’s vegetable consumption falls below current recommendations in many countries. The first approach to increase acceptance of vegetables was based on offering infants a variety of vegetables (purée changed every day for 10 days vs. 3 days and no change) at the beginning of weaning. Such an experience with a variety of foods as of the beginning of weaning is associated with a higher acceptance of new vegetables and new foods from other groups, which persisted for several weeks, and to a higher liking and a higher consumption of new vegetables up to the age of 6 years. The acceptance of new vegetables was also higher in infants who had been breastfed, i.e., who had been likely exposed to a variety of flavors in breast milk. The second approach to increase acceptance is based on repeated exposures to an initially disliked vegetable. This experience markedly increases the acceptance of this vegetable, which becomes as liked as an initially liked vegetable. This presentation revealed the plasticity of young children to the food experience they receive in their first years and the long-term effect of this experience in shaping healthy eating habits.

Kimberley Mallan and Narissa Miller addressed another facet of the parentchild interaction in terms of feeding, focusing in particular on eating behaviors related to appetite regulation and obesity risk, and on parental feeding practices likely to alter appetite regulation, namely nonresponsive feeding practices, which can be of many types. In this area, most of the previous research has been cross-sectional, whereas a bidirectional relationship between parent feeding and child eating has been proposed more recently. The aspects of child eating behaviors discussed in relation to obesity risk were eating in the absence of hunger (which can be measured experimentally), food responsiveness, or satiety responsiveness (which can be measured with an instrument such as the Child Eating Behavior Questionnaire). The presented review summarized findings related to feeding practices that may support (e.g., being responsive to a child’s cues or providing mealtime structure) or undermine (e.g., pressure to eat, instrumental emotional feeding, or restriction) children’s eating behaviors. In summary, this review confirmed that parents’ feeding practices do impact on children’s eating behaviors, but also that children’s eating behaviors influence the feeding practices parents use. Moreover, the presentation was ended by useful tips for responsive feeding practices that were successfully tested in the frame of the NOURISH study conducted in Australia.

The session was concluded by Lisa Fries and Klazine van der Horst who addressed “picky eating” in children, and how it is likely to be modified by parental feeding practices. Picky eating is a broad construct that relates to the perception of a limited diet or food refusals. A recent review of the literature found that picky eaters display several different types of behaviors, among which the most common are neophobia, lower fruit and vegetable intake, food refusals, less enjoyment of eating, and sensory sensitivities. Parental feeding practices may be usefully applied to overcome picky eating behavior in children. For instance, parents could be encouraged to keep trying after a food is refused, as children may need to be exposed to a food several times before it is accepted. Varying the preparation changes a food’s taste, texture, and appearance, and this may help identifying a child’s preferred variants. Conversely, coercive feeding practices such as the use of pressure to eat or using food as rewards should be avoided, as these can create negative associations with the food or meals and lead to food refusals. Instead, caregivers can model eating and enjoying the food. Nonfood rewards, such as praise or stickers, can also be used to encourage children to taste a food without negative outcomes. The presentation of casual reports from social media highlighted how food refusals may be an important matter of concern for parents. Finally, useful tips to avoid or cope with food pickiness were presented, which could apply in a variety of cultural contexts.

The second session focused on What Children Eat . The session compared and contrasted what children eat in both advanced and developing nations. Unlike other regions of the world, economic growth in Asia appears to have not kept pace with the eradication of undernutrition. Christiani Jeyakumar Henry articulated the etiology and causes of undernutrition in Asia and other emerging nations. He articulated that undernutrition was due to the poor access to weaning foods with adequate energy and sufficient palatability. Using human growth during the first 6 months of life, he illustrated that, in many instances, it was not the inadequate protein content in the diet that restricted growth but the poor energy density of the meal. The presentation also focused on the provision of simple diet formulations to meet the energy and palatability of infant foods.

In their presentation, Ciarán Forde, Anna Fogel, and Keri McCrickerd focused on how early life risk factors during the first 1,000 days of life can influence the development of childhood obesity. They focused their presentation on emphasizing the major role that caregivers and the food environment can play in the behavioral transition from the early life risk to the development of obesity. Several examples were highlighted. For example, children who ate their meal at a faster rate (g/min) consumed more energy than those that ate at a slower pace. How children’s food intake can be influenced by the availability of palatable foods was also further emphasized. The authors concluded that a holistic intervention was necessary to combat the escalating prevalence of childhood obesity.

Alison L. Eldridge described the history and background to the FITS (Feeding Infants and Toddlers Study) and KNHS (Kids Nutrition and Health Study) program. The FITS/KNHS are cross-sectional surveys designed to investigate nutrient intakes and eating patterns in infants and children. On most occasions, data from national surveys were used for the analysis. These surveys have been conducted in Australia, China, Mexico, the Philippines, Russia, and the USA. Country presentations on the FITS/KNHS program were made for the following countries: China (Danton Wang), Mexico (Salvador Villalpando-Carrion and Alison L. Eldridge), Philippines (Imelda Angeles-Agdeppa et al.), and the USA (Regan Bailey et al.).

Norimah A. Karim and Nurliyana Abdul Razak drew on 2 nationwide studies conducted in Malaysia, SEANUTS Malaysia (the Southeast Asian Nutrition Survey) and the MyBreakfast Study, to make their presentation. They demonstrated that 13–17% of children aged between 6 and 12 years were either overweight or obese. A majority of children attained the Malaysian recommended nutrient intake (RNI) for energy and protein. However, RNI for calcium and vitamin D was not met by more than half of the children. They also showed that only 13.4 and 9.5% met the Malaysian Dietary Guideline (MDG) for fruit and vegetable intake per day, respectively. The MyBreakfast Study showed that approximately 18% of the children consumed ready-to-eat cereal at breakfast. Milk, dairy products, and fruits and vegetables were not daily eaten; only 1 in 20 children met the MDG for milk while 1 in 10 achieved the MDG for fruits and vegetables. It was concluded that there is considerable scope for improving the fruit/vegetable and milk consumption in this age group.

The third and final session focused on revisiting the Importance of Breakfast for Children’s Health and Development. Breakfast has long been promoted as the most important meal of the day. However, the lack of standard definitions of breakfast, breakfast consumers, and breakfast skippers, and the lack of a description of how the meal is important, especially compared with other meals, have hampered the ability to confirm this long-held belief. All of the inconsistencies in these definitions can affect how researchers, nutrition educators, and policy makers interpret data and make recommendations. Mike Gibney and Irina Uzhova’s presentation focused on dietary guidelines for breakfast intakes. Whilst there is consistent evidence on the nutritional benefits of a regular breakfast, there are few guidelines to help policy makers issue specific targets on optimal nutrient intake at breakfast or selection of foods to possibly include in the development of a nutritious breakfast. However, there is a lack of consistency in the definition of recommended food categories. Collectively, government recommendations that are currently being used highlight the need for a more scientifically rigorous approach to recommend optimal food and nutrient intakes at breakfast. Cluster analysis is one approach in determining optimal nutrient and food intake. However, there are major limitations in setting out gradations in optimal nutrient intakes for breakfast. Ultimately, meal-based advice may become the basic building block for digitally based personalized dietary analysis and guidelines.

Leonidas Karagounis discussed the importance of dietary protein at breakfast in childhood. Proteins are the major functional and structural components of all the cells of the body and participate in virtually all biological processes occurring in the body. Dietary protein is essential in child nutrition because children are in a state of ongoing growth and development. In terms of nutrient availability, current research supports the concept of nutrient timing intake. For example, the diurnal turnover of whole body protein which in turn impacts whole body protein balance may to some extent be dictated by specific need states where macronutrient intake, such as proteins and carbohydrates, may be imperative to support healthy physical growth and development. Specifically, a typically observed overnight fast in children has recently been shown to result in a physiological state of increased catabolism as measured by increased rates of whole body protein breakdown. It is, therefore, important that specific amounts of macronutrients be consumed at breakfast in order to attenuate such losses in whole body protein and, therefore, to provide an environment that supports healthy physical growth and development.

Theresa A. Nicklas presented 3 studies looking at breakfast skipping and body weight, breakfast patterns, and breakfast cognition. Twenty percent of US children and 32% of US adolescents skipped breakfast. Breakfast skippers had the lowest mean adequacy ratio for micronutrients compared to those who consumed breakfast. Moreover, breakfast skippers had the highest body mass index. They acknowledged a limitation of this study, which, among other similar studies, has been based on the incorrect premise that breakfast meals are homogeneous. A separate study found 12 distinct breakfast patterns in a US nationally representative sample of children. Results suggest that simply consuming breakfast was not associated with better diet quality when compared to breakfast skippers. More importantly, the specific foods/food groups consumed at breakfast influenced nutrient intake and overall diet quality. Thus, the nutrient profiles varied considerably depending on the type of breakfast pattern. The association of the breakfast patterns was not consistently associated with lower body mass index as seen in breakfast skippers. The third study was designed to address inconsistencies observed in previous studies by examining the short-term effects of breakfast consumption and fasting on neuropsychological functioning using a robust set of psychological measures of multiple domains of cognitive functioning in healthy, low- and medium-income school-age children. Breakfast consumption had no effect on neuropsychological functioning in children. More studies are needed regarding habitual breakfast consumption and its effect on neuropsychological functioning in healthy children and those with marginal or subnormal nutritional status.

The session was concluded by Sandra I. Sünram-Lea, who reviewed the impact of breakfast-based glycemic response on cognition in children. The data suggest that a more stable blood glucose profile which avoids greater peaks and troughs in circulating glucose is associated with better cognitive function across the morning. Although the evidence to date is promising, it is currently insufficient to allow firm and evidence-based recommendations. What limits our ability to draw conclusions from previous findings is that the studies have differed widely with respect to subject characteristics, cognitive tests used, and timing of cognitive assessment. In addition, few studies have profiled glycemic response in children specifically.

Christiani J. Henry

Theresa A. Nicklas

Sophie Nicklaus