title: Galacto-oligosaccharides are bifidogenic and safe at weaning: a double-blind randomized multicenter study.
abstract: OBJECTIVE
  The primary objective of this study was to determine the bifidogenic effect of galacto-oligosaccharides (GOS) in a follow-on formula and the effects on other intestinal bacteria. Secondary objectives were the effects on stool characteristics, growth, and general well-being.
  
  
  METHODS
  In a multicenter, double-blind study, 159 healthy infants, formula-fed at enrollment (at 4-6 months), were randomized to an experimental follow-on formula supplemented with 5 g/L (GOS) (77 infants), or to a standard follow-on formula (control, 82 infants). Infants were evaluated at enrollment (study day 1 = sd1), after 6 weeks (study day 2 = sd2), and after an additional 12 weeks (study day 3 = sd3). At each study day, a fresh stool sample for the bacterial counts was collected, and the growth parameters were measured. At sd2, urinary specimens were collected for the evaluation of urinary osmolarity.
  
  
  RESULTS
  At sd2 and sd3, the GOS group had a higher median number (colony-forming units per gram of stool) of bifidobacteria than did the control group (sd2 GOS 9.2 x 10(9) vs control 4.4 x 10(9), P = 0.012); (sd3 GOS 7.2 x 10(9) vs control 2.4 x 10(9), P = 0.027). Other bacteria did not show any significant differences between the 2 groups at all study days. The GOS produced softer stools but had no effect on stool frequency. The urinary osmolarity (mOsm/L) at sd2 was comparable in both groups. Supplementation had no influence on the incidence of gastrointestinal side effects or on the growth of the infants.
  
  
  CONCLUSIONS
  These data indicate that the addition of GOS (5 g/L) to a follow-on formula positively influences the bifidobacteria flora and the stool consistency in infants during the supplementation period at weaning. No local or systemic side effects were recorded.
authors.affiliation: Neonatal Intensive Care Unit, University of Ferrara, Ferrara, Italy. fnrslv@unife.it
authors.forename: Silvia
authors.initials: S
authors.lastname: Fanaro
authors.forename: Berit
authors.initials: B
authors.lastname: Marten
authors.forename: Rossana
authors.initials: R
authors.lastname: Bagna
authors.forename: Vittorio
authors.initials: V
authors.lastname: Vigi
authors.forename: Claudio
authors.initials: C
authors.lastname: Fabris
authors.forename: Luis
authors.initials: L
authors.lastname: Peña-Quintana
authors.forename: Federico
authors.initials: F
authors.lastname: Argüelles
authors.forename: Katharina E
authors.initials: KE
authors.lastname: Scholz-Ahrens
authors.forename: Günther
authors.initials: G
authors.lastname: Sawatzki
authors.forename: Richard
authors.initials: R
authors.lastname: Zelenka
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schrezenmeir
authors.forename: Michael
authors.initials: M
authors.lastname: de Vrese
authors.forename: Enrico
authors.initials: E
authors.lastname: Bertino
mesh_terms: D001644:Bifidobacterium / Q000187:drug effects / Q000254:growth & development*; D015169:Colony Count, Microbial; D004311:Double-Blind Method; D005243:Feces / Q000382:microbiology; D005260:Female; D005690:Galactose / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D007223:Infant; D041943:Infant Formula / Q000008:administration & dosage*; D007422:Intestines / Q000382:microbiology; D008297:Male; D009844:Oligosaccharides / Q000008:administration & dosage* / Q000009:adverse effects; D009994:Osmolar Concentration; D010919:Placebos; D014556:Urine; D014886:Weaning
chemical_list: D009844:Oligosaccharides; D010919:Placebos; D005690:Galactose