Human milk protein does not limit growth of breast-fed infants.

BACKGROUND The efficiency with which breast- and formula-fed infants utilize dietary nutrients is likely to provide insight into their relative requirements for the growth process. METHODS We measured longitudinal changes in growth, body composition, and dietary intakes in breast- and formula-fed infants and estimated the gross efficiency with which dietary nitrogen and energy were used for lean body mass and body fat deposition. Lean body mass and body fat were determined in 10 breast-fed and 10 formula-fed infants at 6-week intervals during the first 24 weeks of life by the 18O dilution technique. Dietary nitrogen and energy intakes were determined from the amount of milk and food consumed and the nutrient content of the feedings. The gross efficiency of nutrient utilization was calculated for each infant from the cumulative dietary intake and the change in body composition with time. RESULTS Length and weight gains and lean body mass and body fat accretion during the first 24 weeks of life were similar between breast- and formula-fed infants despite significantly higher nitrogen and energy intakes of the formula-fed group. The gross efficiency of dietary nitrogen utilization for lean body mass deposition was almost two-fold lower in formula- than in breast-fed infants, whereas the efficiency of dietary energy utilization for lean body mass and body fat deposition was similar between groups. Despite apparent differences in the efficiency of nitrogen utilization, there was no association between lean body mass deposition and dietary protein intake, implying that human milk protein does not limit growth quantitatively in breast-fed infants. CONCLUSIONS These differences in nutrient utilization illustrate the biologic adaptability of human infants who are equipped with mechanisms that promote normal growth despite the variability of their nutrient intake.

[1]  K. Michaelsen,et al.  Growth of breast-fed infants deviates from current reference data: a pooled analysis of US, Canadian, and European data sets. World Health Organization Working Group on Infant Growth. , 1995, Pediatrics.

[2]  S. Amini,et al.  An Analysis of Birth Weight by Gestational Age Using a Computerized Perinatal Data Base, 1975–1992 , 1994, Obstetrics and gynecology.

[3]  M. Heinig,et al.  Breast-fed infants are leaner than formula-fed infants at 1 y of age: the DARLING study. , 1993, The American journal of clinical nutrition.

[4]  B. Nichols,et al.  Nutrient intake and growth performance of older infants fed human milk , 1989 .

[5]  G. Beaton,et al.  Protein requirements of infants: a reexamination of concepts and approaches. , 1988, The American journal of clinical nutrition.

[6]  L. Eggert,et al.  Birth weights in term infants. A 50-year perspective. , 1988, The Journal of reproductive medicine.

[7]  R. Shepherd,et al.  Longitudinal study of the body composition of weight gain in exclusively breast-fed and intake-measured whey-based formula-fed infants to age 3 months. , 1988, Journal of pediatric gastroenterology and nutrition.

[8]  M. Fiorotto,et al.  Fat-Free Mass and Total Body Water of Infants Estimated from Total Body Electrical Conductivity Measurements , 1987, Pediatric Research.

[9]  E. Forsum,et al.  Growth, body composition and breast milk intake of Swedish infants during early life. , 1986, Early human development.

[10]  B. Nichols,et al.  Formula Intake of 1− and 4‐Month-Old Infants , 1986, Journal of pediatric gastroenterology and nutrition.

[11]  M. Siimes,et al.  Exclusively Breast-Fed Healthy Infants Grow Slower than Reference Infants , 1985, Pediatric Research.

[12]  R. Whitehead,et al.  Growth charts and the assessment of infant feeding practices in the western world and in developing countries. , 1984, Early human development.

[13]  B. Duncan,et al.  Reduced growth velocity in exclusively breast-fed infants. , 1984, American journal of diseases of children.

[14]  N. Butte,et al.  Effect of maternal diet and body composition on lactational performance. , 1984, The American journal of clinical nutrition.

[15]  B. Nichols,et al.  Human milk intake and growth in exclusively breast-fed infants. , 1984, The Journal of pediatrics.

[16]  F. Haschke,et al.  Body composition of reference children from birth to age 10 years. , 1982, The American journal of clinical nutrition.

[17]  M. Gracey,et al.  GROWTH OF HEALTHY BREAST-FED INFANTS IN THE FIRST SIX MONTHS , 1981, The Lancet.

[18]  R. Whitehead,et al.  INFANT GROWTH AND HUMAN MILK REQUIREMENTS A Fresh Approach , 1981, The Lancet.

[19]  W. Maclean,et al.  Growth of the exclusively breast-fed infant. , 1980, The American journal of clinical nutrition.

[20]  Cantab Mb.  Christopher George Attenborough. , 1979 .

[21]  O. Brooke,et al.  Fetal growth in different racial groups. , 1978, Archives of disease in childhood.

[22]  J. Oakley.  Differences in subcutaneous fat in breast- and formula-fed infants. , 1977, Archives of disease in childhood.

[23]  M. Flynn,et al.  A Longitudinal Study of Total Body Potassium in Normal Breastfed and Bottle-fed Infants , 1976, Pediatric Research.

[24]  J. Robson,et al.  Growth standards for infants and children: a cross-sectional study. , 1975, Pediatrics.

[25]  L. Filer,et al.  FOOD CONSUMPTION AND GROWTH OF NORMAL INFANTSFED MILK‐BAS ED FORMULAS , 1971 .

[26]  K. Jeejeebhoy,et al.  Determination of fecal fats containing both medium and long chain triglycerides and fatty acids. , 1970, Clinical biochemistry.

[27]  D. Southgate,et al.  The intake and excretion of calorific constituents of milk by babies , 1966, British Journal of Nutrition.

[28]  Chen St.  Growth of weight, length and crown-rump length of Malaysian infants and pre-school children. , 1990 .

[29]  P. Klein,et al.  In vivo isotope-fractionation factors and the measurement of deuterium- and oxygen-18-dilution spaces from plasma, urine, saliva, respiratory water vapor, and carbon dioxide. , 1988, The American journal of clinical nutrition.