ENERGY-REQUIREMENTS FOR GROWTH AND DEVELOPMENT IN INFANCY

Current international recommendations for energy requirements are base d on > 9000 measurements of energy intake in both breast- and formula- fed infants. The measurement of energy intake in babies is far from st raightforward and the possibility of significant error is great. The o pportunity now exists, however, to compare current recommendations wit h measurements of total energy expenditure (TEE) obtained via the doub ly labeled water technique. Approximately 300 measurements of TEE in t he first year of life have been made in normal, healthy babies. These data show that estimates of energy intake derived from the measurement s of TEE are considerably below the current international recommendati ons. The same technique has also allowed the energy requirements of si ck infants to be evaluated. Two examples are highlighted of infants bo rn small for gestational age and infants born with cystic fibrosis. Fi rst, data collected from babies born small for gestational age suggest that such infants have a TEE and hence requirement approximate to 20% above that found in infants born with a weight appropriate for their gestational age. This information will be relevant to those profession als attempting to supply optimum nutrition to babies born small for ge stational age. Second, in cystic fibrosis it has been suggested that, concurrent with the basic features of the disease, there is an energy- wasting lesion that will increase TEE and hence energy requirement. Re cent data collected from babies with cystic fibrosis strongly suggest that this is not the case, and previous data were confounded by subcli nical disease status.