Eating behavior development in infants

Currently, 1/3 of children and 2/3 of adults are overweight/obese. While the social ecological model identifies many factors affecting the development of obesity, there is a lack of understanding of the individual-level differences that are contributing to this risk. The parent grant will identify infant eating behavior phenotypes that are associated with rapid infant weight gain, such as poor satiety responsiveness, increased working for food, and the soothing and hedonic effects of sucrose. While they will examine potential predictors of these behaviors, e.g., maternal obesity, eating behavior, diet, and stress, they do not examine individual level biologic differences that may be contributing to these infant eating behaviors. In this proposal, we will focus on the gut microbiome. The composition and diversity of the gut microbiome has been associated with weight status, and can affect one’s metabolism, physiology, and behavior. As such, our goal is to examine the relationship between the infant gut microbiome and fecal metabolomics to early infant eating behaviors and weight gain trajectory during the first year of life. We will collect stool samples and examine the microbial composition and diversity of 325 infant-mother dyads at 2 weeks, 4 months, 6 months, 9 months, and 12 months of life. We will examine how baseline composition and diversity of the gut microbiome, as well as changes in this biome, relate to infant eating behaviors (particularly satiety responsiveness, working for food, and the soothing and hedonic effects of sucrose) and weight gain trajectory during this time frame. With the mother’s microbiome as well as her and the infant’s dietary, perinatal, and medical history, we will also examine factors that affect the development of the infant microbiome. 16S rRNA and fecal metabolomics will be used to identify the composition and diversity of this gut microbiome and its byproducts. This work will lay the groundwork for future exploration of microbial-gene interactions and how the microbiome may be affecting hormonal and neurologic control of eating behaviors. Ultimately, this work will contribute to the basic biologic understanding of eating behaviors that are contributing to the development of abnormal weight gain trajectories and identify potential targets of intervention.