Research on the safety and efficacy of probiotic supplementation is on-going. To date, there are many knowledge gaps due to few studies proving that probiotics are impactful on our health. Research is growing with respect to using a specific combination of probiotics in preterm, low-birth-weight infants born before 37 weeks gestation for the prevention of necrotizing enterocolitis. Even with the research, probiotics are not appropriate for all preterm, low-birth-weight infants.