BACKGROUND: The metabolic response to different protein intakes from breast milk and/or formulas varying in protein concentrations, in combination with supplementary foods, has not been studied in @entity1 who are in the second half of infancy. METHODS: Healthy @entity1 , exclusively breast-fed until 3 months old, were randomly assigned to one of three groups, F13, F15, or @entity29786 , and were given formulas with 13, 15, or 18 g/l of protein, respectively. @entity1 breast-fed (B) and mixed-fed (M) (breast milk and formula) at 6 months formed the fourth and fifth groups. All @entity1 received the same supplementary foods and were studied from ages 3 to 12 months. RESULTS: The concentrations of albumin, prealbumin, and @entity69 were similar in all groups. At 6 months, serum and urine @entity1133 concentrations were lower in B and M, compared with @entity1133 levels in the formula-fed groups of @entity1 . At 12 months, urine @entity1133 was lower in B + M than it was in @entity29786 . At 6 months, plasma concentrations of @entity815 , @entity669 , and @entity1853 were higher in all formula-fed groups; and those of @entity4857 . @entity6778 , and @entity1889 were higher in @entity29786 and F15 than they were in B and M. Plasma concentrations of @entity1853 , @entity4857 , and @entity1889 were higher in @entity29786 than in F13. At 12 months, plasma levels of @entity669 , @entity1853 , @entity4857 , @entity6778 , and @entity368 were higher in @entity29786 than they were in B + M. CONCLUSION: Many indexes of protein metabolism were similar in groups F13, B, and M, particularly at 6 months. In contrast, the provision of a formula with 18 g/l of protein resulted in a different metabolic pattern, which could indicate unnecessarily high protein intakes.

Protein and amino acid metabolism in three- to twelve-month-old XXXX fed @entity1 milk or formulas with varying protein concentrations.

@entity1 :: ('9606', 'Species') :: ['infants', 'Infants'] @entity1133 :: ('MESH:D014508', 'Chemical') :: ['urea'] @entity368 :: ('CHEBI:25017', 'Chemical') :: ['leucine'] @entity69 :: ('7018', 'Gene') :: ['transferrin'] @entity1853 :: ('MESH:D008715', 'Chemical') :: ['methionine'] @entity6778 :: ('CHEBI:24898', 'Chemical') :: ['isoleucine'] @entity4857 :: ('CHEBI:27266', 'Chemical') :: ['valine'] @entity1889 :: ('CHEBI:26986', 'Chemical') :: ['threonine'] @entity815 :: ('CHEBI:28044', 'Chemical') :: ['phenylalanine'] @entity669 :: ('CHEBI:18186', 'Chemical') :: ['tyrosine'] @entity29786 :: ('10046', 'Gene') :: ['F18']
@entity1 :: (9606,Species) :: ['infants']
