Gut Pathog. 2009 Mar 19;1(1):6.

A randomized, double-blind, placebo-controlled

pilot study of a probiotic in emotional symptoms

of chronic fatigue syndrome.

Rao AV, Bested AC, Beaulne TM, Katzman MA, Iorio

C, Berardi JM, Logan AC.

Integrative Care Centre of Toronto, 3600 Ellesmere

Road, Unit 4, Toronto, Ontario M1C 4Y8, Canada.

aclnd@cfs-fm.org.

ABSTRACT:

Chronic fatigue syndrome (CFS) is complex illness of

unknown etiology. Among the broad range of

symptoms, many patients report disturbances in the

emotional realm, the most frequent of which is

anxiety.

Research shows that patients with CFS and other

so-called functional somatic disorders have

alterations in the intestinal microbial flora.

Emerging studies have suggested that pathogenic

and non-pathogenic gut bacteria might influence

mood-related symptoms and even behavior in

animals and humans.

In this pilot study, 39 CFS patients were randomized

to receive either 24 billion colony forming units of

Lactobacillus casei strain Shirota (LcS) or a placebo

daily for two months.

Patients provided stool samples and completed the

Beck Depression and Beck Anxiety Inventories before

and after the intervention.

We found a significant rise in both Lactobacillus and

Bifidobacteria in those taking the LcS, and there was

also a significant decrease in anxiety symptoms

among those taking the probiotic vs controls (p =

0.01).

These results lend further support to the presence of

a gut-brain interface, one that may be mediated by

microbes that reside or pass through the intestinal

tract.