Grant: Project Grant

Early infancy is a critical period for growth and development, during which milk provides most of the energy infants need. A large portion of this energy comes from milk fat. However, newborns, and especially premature infants, have limited ability to digest and absorb fat because their digestive systems are still immature. Poor fat absorption can contribute to slower growth and other health challenges, yet the biological factors that support fat use in early life are not fully understood. This project explores a previously unrecognized contributor to infant nutrition: gut fungi. Using data from infant cohorts and experimental models, our research has identified Malassezia, a group of fungi that depend on fats for growth, as a consistent but temporary resident of the infant gut during the period when infants consume only milk. We have shown that Malassezia can grow in breast milk and infant formula when fat is present, and that animals colonized with these fungi gain weight more rapidly early in life. These findings suggest that Malassezia may help process milk fat into forms that are easier for infants to absorb. The goal of this study is to determine whether Malassezia directly contributes to milk fat digestion and absorption during early life. We will examine how these fungi interact with milk fats, how they influence fat uptake by the intestine, and whether their presence in infants is linked to improved fat absorption and growth, particularly in premature infants. By uncovering a new role for gut fungi in early-life nutrition, this research may lead to new strategies to support healthy growth in infants who struggle with fat absorption and improve nutritional care for vulnerable newborns.