Objective To examine whether long term consumption of a probiotic milk could reduce gastrointestinal and respiratory infections in children in day care centres. Design Randomised, double blind, placebo controlled study over seven months. Setting 18 day care centres in Helsinki, Finland. Participants 571 healthy children aged 1-6 years: 282 (mean (SD) age 4.6 (1.5) years) in the intervention group and 289 (mean (SD) age 4.4 (1.5) years) in the control group. Intervention Milk with or without Lactobacillus GG. Average daily consumption of milk in both groups was 260 ml. Main outcome measures Number of days with respiratory and gastrointestinal symptoms, absences from day care because of illness, respiratory tract infections diagnosed by a doctor, and course of antibiotics. Results Children in the Lactobacillus group had fewer days of absence from day care because of illness (4.9 (95% confidence interval 4.4 to 5.5) v 5.8 (5.3 to 6.4) days, 16% difference, P = 0.03; age adjusted 5.1 (4.6 to 5.6) v 5.7 (5.2 to 6.3) days, 11% difference, P = 0.09). There was also a relative reduction of 17% in the number of children suffering from respiratory infections with complications and lower respiratory tract infections (unadjusted absolute % reduction − 8.6 ( − 17.2 to − 0.1), P = 0.05; age adjusted odds ratio 0.75 (0.52 to 1.09), P = 0.13) and a 19% relative reduction in antibiotic treatments for respiratory infection (unadjusted absolute % reduction − 9.6 ( − 18.2 to − 1.0), P = 0.03; adjusted odds ratio 0.72 (0.50 to 1.03), P = 0.08) in the Lactobacillus group. Conclusions Lactobacillus GG may reduce respiratory infections and their severity among children in day care. The effects of the probiotic Lactobacillus GG were modest but consistently in the same direction.

With these real-time PCR assays, quantitative alterations in the GI microbiota of IBS patients were found. Increasing microbial DNA sequence information will further allow designing of new real-time PCR assays for a more extensive analysis of intestinal microbes in IBS.

L. helveticus LBK-16H fermented milk containing bioactive peptides in normal daily use has a blood pressure-lowering effect in hypertensive subjects.