In spite of a number of studies on necrotizing enterocolitis, there remains controversy concerning prevention regimens, especially with regard to enteral alimentation. This report is of a matched case-control study of the relationship of necrotizing enterocolitis to timing of first feeding, size of feeding volumes and increments, and a risk factor index in 59 case patients with necrotizing enterocolitis and 59 matched control patients. Comparison with control patients showed that case patients were fed earlier, received full-strength formula sooner, and received larger feeding volumes and increments. More highly stressed infants, as measured by the risk index, were more vulnerable to larger feeding increments. Among case patients there was significant correlation of age at first feeding and age at diagnosis (p < 0.0001) even after control for birth weight and risk index score, indicating that delayed feeding was related to delayed onset of disease. These analyses support the theory that earlier, more rapid feeding places stressed infants at greater risk for the development of necrotizing enterocolitis, and that infants with more severe respiratory problems are more vulnerable to such feeding practices.