She has been studying intestinal microbiology and immunology for the past 10 years. Her recent study connecting asthma in very young babies to missing key intestinal bacterial species was deemed a breakthrough in the field and was reported by dozens of news outlets around the world in 2015. Arrieta has been published in leading scientific journals such as Gastroenterology, PNAS, and Science Translational Medicine. She spends her busy days juggling between experiments, science writing, kindergarten pick-ups, and play dates for her two young children.