this article reviews the current understanding of enteral and parenteral nutrition therapy in preterm infants, with an emphasis on very low birth weight babies. the protective effects of nutrition therapy against neonatal sepsis and necrotizing enterocolitis are discussed. different methods of feeding preterm infants are evaluated. special attention is given to the problems of very low birth weight babies and the protective effects of nutrition to counteract complications, especially infection. the preferential use of breast milk for enteral nutrition, the management of protein and energy offers, the use of early and minimal enteral nutrition, the early introduction of parenteral nutrition (within the first 24 hours of life) and the use of immunonutrients that are appropriately supported by a sufficient number of studies can provide good adjuvant therapy guidelines to prevent neonatal sepsis and necrotizing enterocolitis. however, we conclude that additional multicenter, randomized controlled studies are necessary to clarify the protective role of nutrition in preterm infants. appropriate nutrition is not only effective in treating and preventing infective complications, but it also promotes neurodevelopment and prevents future harmful consequences.