Grant: Doctoral Re. Award - PA: Sex, Gender and Intersectionality in Health Research

Early childhood is a crucial period of growth and development that shapes long-term health. During this time, the gut microbiome, comprising bacteria and other microbes that reside in the gut, develops and is believed to support the maturation of the body's immune and nervous systems. Diet strongly influences which microbes thrive, and poor nutrition can disrupt the microbiome in ways that raise disease risk in childhood and later life. While research has shown that gut bacteria play a significant role in linking diet and health, important questions remain, such as their specific role in early brain and behavioral development, whether boys and girls respond differently to microbiome changes, and how bacterial functions may help predict future health outcomes. My research examines the relationship between the gut microbiome and child development and health in early life, utilizing advanced tools to investigate the diversity of bacteria, their functions, and the compounds they produce. In Chapter 1, I investigate whether drinking toddler formula, cow's milk, or no milk has an impact on gut bacteria and their function, and whether these changes affect behavior differently in boys and girls. In Chapter 2, I use data from a large Canadian birth cohort study to examine whether bacterial functions gained in the first year of life influence child behavior at 5 years-of-age, and whether breastfeeding plays a role in promoting beneficial bacterial functions. In Chapter 3, I study children who have lost part of their bowel with the aim of finding bacterial species or functions that indicate whether a child is recovering from the bowel loss or if they need ongoing nutritional support. A better understanding of how diet shapes gut bacteria, and how these bacteria in turn affect children's long-term health, can guide new research on dietary recommendations to support optimal brain and immune development, and inform future therapeutic strategies in clinical care.