PEMT and cystic fibrosis: Choline is a critical nutrient in the overall population, particularly in several vulnerable groups at risk for deficiency, such as preterm infancy (PI), cystic fibrosis (CF) with exocrine pancreatic insufficiency, long-term total parenteral nutrition (TPN), small intestine bacterial overgrowth (SIBO) resulting in intestinal choline degradation prior to absorption, and frequent SNPs of the PEMT gene [7].