Randomized comparison of a nutrient-dense formula with an energy-supplemented formula for infants with faltering growth

Introduction The practice of supplementing standard infant formula with energy for infants with faltering growth has been widespread. This increases energy density but disturbs the pro- tein : energy ratio, and increases risks of microbial contamination and errors in feed preparation. This study aimed to compare the effectiveness of a nutrient-dense formula (NDF) with an energy-supplemented formula (ESF) in infants with faltering growth. Methods in an open, parallel, randomized study, 49 infants with faltering growth were randomized to receive a NDF (4.2 kJ mL(-1)) or an ESF (4.2 kJ mL-1), for 6 weeks. Anthropometry, biochemistry, feed intake, stool and vomit frequency were collected. Results No significant differences in tolerance, feed volumes or energy intakes were recorded but the NDF group received 42% more protein and 15-40% more vitamins and minerals. Blood urea concentration in the ESF group fell by 50% over the trial period, suggesting a suboptimal protein : energy ratio in the ESF feed. The NDF group retained a normal mean blood urea concentration, a higher urinary potassium concentration and did not have the significant fall in length z-score seen in the ESF group. Conclusion Increasing the energy content of normal infant formula without also increasing protein and micronutrients should not be practiced in infants with faltering growth.