Effect of a probiotic infant formula on infections in child care centers: comparison of two probiotic agents.
Weizman Z, Asli G, Alsheikh A. 2005.
Summary and comments by Mary Ellen Sanders, Ph.D.
Keeping healthy people healthy (or making them even healthier) is the bedrock hope for probiotics. Although there are many cases documenting the therapeutic benefit of probiotic intervention (managing symptoms of rotavirus diarrhea, inflammatory bowel disease, irritable bowel syndrome and allergy), establishing the role of probiotics in health maintenance must be better understood. A recent study in the journal Pediatrics demonstrates the ability of two probiotic bacteria (Bifidobacterium lactis BB12 or Lactobacillus reuteri ATTC55730) to help prevent diarrhea and fever, but not respiratory illnesses. This study was conducted with 201 healthy, formula-fed infants 4-10 months of age at 14 child care centers in Israel. Primary outcome measures were frequency and duration of fever, diarrhea or respiratory illness. In addition the following were measured: number of visits to the clinic, number of antibiotic prescriptions, absences from child care center, growth parameters, daily number of meals, regurgitation, vomiting, stool pathogens, and changes in behavior and stool characteristics. The 12-week study was blinded and placebo-controlled comparing the control group to infants fed B. lactis or L. reuteri at levels of ~1.2×109 CFU/d.
Infants fed formula containing probiotics had fewer days and episodes of fever, days and episodes of diarrhea, clinic visits and absences from child care centers. L. reuteri-supplemented formula was more effective than B. lactis-supplemented formula. The authors note, however, that although the differences were statistically significant, their clinical impact may be minor. The differences observed in duration of fever and diarrhea, for example, was less than one day.
This study provides insight into the type and degree of impact different probiotic strains might have on maintaining the health of infants in day care settings. The study was well controlled and the comparison between 2 different types of probiotics is especially valuable to our understanding of strain-specific effects.