Increasing work-place healthiness with the probiotic Lactobacillus reuteri: a randomised, double-blind placebo-controlled study.

Environ Health. 4:25.

Tubelius P, Stan V, Zachrisson A. 2005.

Although improved immune function has been documented for many probiotic strains, what has been lacking is compelling evidence that correlates these results with improving a person's ability to stay healthy. After all, most people aren't as interested in, for example, how activated their macrophages might be as they are in keeping from getting sick. In recent months, several papers have been published documenting that probiotics decrease absences from the workplace or day care and the symptoms and occurrences of common illnesses (see list below). In our feature paper, Tubelius et al. (2005) conducted a randomized, placebo-controlled study in Sweden with 181 healthy, adult workers to see if probiotic consumption could reduce workplace absences during an 80 day study. Workers were divided into either the test or placebo groups. The test group received dried 10⁸ CFU/ml L. reuteri ATCC55730 per day dispensed in a drinking straw together with at least 100 ml liquid.

The study found that the number of workers absent was lower in the L. reuteri consuming group (10.6%) than in the placebo group (26.4%) (p<0.01). The frequency of sick-days was 0.9% in the placebo group and 0.4% in the L. reuteri group (p<0.01). Among the 53 shift-workers, 33% in the placebo group reported sick during the study period as compared with none in the L. reuteri group (p<0.005). However, the median duration of sick leave among the subjects who reported any sick leave was equal in the two groups (3 days).

Although immune parameters of subjects were not tested in this study, a possible hypothesis is that probiotic-induced, enhanced immune function allowed these workers to avoid the illness that impacted their coworkers.

Of note in this study was the dose of probiotic that was delivered, 10⁸ CFU/d. Studies showing positive health effects at this level of feeding are not common; most studies deliver 10⁹, 10¹⁰ or even more CFU each day. However, several studies with L. reuteri have shown positive alterations in some biomarkers in addition to this positive clinical trial at this dose.

Some other recent studies documenting that some probiotic strains or strain blends can keep healthy people healthy include:

• de Vrese M, Winkler P, Rautenberg P, Harder T, Noah C, Laue C, Ott S, Hampe J, Schreiber S, Heller K, Schrezenmeir J. Clin Nutr. 2005 Aug;24(4):481-91. Effect of Lactobacillus gasseri PA 16/8, Bifidobacterium longum SP 07/3, B. bifidum MF 20/5 on common cold episodes: a double blind, randomized, controlled trial.
• Weizman Z, Asli G, Alsheikh A. Pediatrics. 2005 Jan;115(1):5-9.Effect of a probiotic infant formula on infections in child care centers: comparison of two probiotic agents.
• Winkler P, de Vrese M, Laue Ch, Schrezenmeir J. Effect of a dietary supplement containing probiotic bacteria plus vitamins and minerals on common cold infections and cellular immune parameters. Int J Clin Pharmacol Ther. 2005 Jul;43(7):318-26.
• Turchet P, Laurenzano M, Auboiron S, Antoine JM. Effect of fermented milk containing the probiotic Lactobacillus casei DN-114001 on winter infections in free-living elderly subjects: a randomised, controlled pilot study. J Nutr Health Aging. 2003;7(2):75-7.
• Hatakka K, Savilahti E, Ponka A, Meurman JH, Poussa T, Nase L, Saxelin M, Korpela R. BMJ. 2001, 2;322(7298):1327. Effect of long term consumption of probiotic milk on infections in children attending day care centres: double blind, randomised trial.