title: Increased protein intake augments kidney volume and function in healthy infants.
abstract: Protein intake has been directly associated with kidney growth and function in animal and human observational studies. Protein supply can vary widely during the first months of life, thus promoting different kidney growth patterns and possibly affecting kidney and cardiovascular health in the long term. To explore this further, we examined 601 healthy 6-month-old formula-fed infants who had been randomly assigned within the first 8 weeks of life to a 1-year program of formula with low-protein (LP) or high-protein (HP) contents and compared them with 204 breastfed (BF) infants. At 6 months, infants receiving the HP formula had significantly higher kidney volume (determined by ultrasonography) and ratios of kidney volume to body length and kidney volume to body surface area than did infants receiving the LP formula. BF infants did not differ from those receiving the LP formula in any of these parameters. Infants receiving the HP formula had significantly higher serum urea and urea to creatinine ratios than did LP formula and BF infants. Hence, in this European multicenter clinical trial, we found that a higher protein content of the infant formula increases kidney size at 6 months of life, whereas a lower protein supply achieves kidney size indistinguishable from that of healthy BF infants. The potential long-term effects of a higher early protein intake on long-term kidney function needs to be determined.
authors.affiliation: Pediatrics Unit, Universitat Rovira i Virgili, Reus, Spain.
authors.forename: Joaquin
authors.initials: J
authors.lastname: Escribano
authors.forename: Veronica
authors.initials: V
authors.lastname: Luque
authors.forename: Natalia
authors.initials: N
authors.lastname: Ferre
authors.forename: Marta
authors.initials: M
authors.lastname: Zaragoza-Jordana
authors.forename: Veit
authors.initials: V
authors.lastname: Grote
authors.forename: Berthold
authors.initials: B
authors.lastname: Koletzko
authors.forename: Dariusz
authors.initials: D
authors.lastname: Gruszfeld
authors.forename: Piotr
authors.initials: P
authors.lastname: Socha
authors.forename: Elena
authors.initials: E
authors.lastname: Dain
authors.forename: Jean-Noel
authors.initials: JN
authors.lastname: Van Hees
authors.forename: Elvira
authors.initials: E
authors.lastname: Verduci
authors.forename: Ricardo
authors.initials: R
authors.lastname: Closa-Monasterolo
mesh_terms: D000367:Age Factors; D000375:Aging; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D001827:Body Height; D001830:Body Surface Area; D001942:Breast Feeding; D003404:Creatinine / Q000097:blood; D018753:Diet, Protein-Restricted; D004044:Dietary Proteins / Q000008:administration & dosage* / Q000378:metabolism; D004311:Double-Blind Method; D005060:Europe; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007223:Infant; D041943:Infant Formula; D007668:Kidney / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000378:metabolism; D016014:Linear Models; D008297:Male; D009929:Organ Size; D014463:Ultrasonography; D014508:Urea / Q000097:blood
chemical_list: D015415:Biomarkers; D004044:Dietary Proteins; D014508:Urea; D003404:Creatinine