A new study shows that a probiotic available commercially in the US for fortifying the digestive system, has effects beyond the gastrointestinal tract: it may also have effects against non-gut inflammation such as in psoriasis and chronic fatigue syndrome (CFS).

The study, published in the latest issue of the journal Gut Microbes is thought to be important because it is the first to show a single probiotic can influence not only the mucosal immune system but also the systemic immune system in humans.

The mucosal immune system protects the internal mucosal surfaces of the body such as the gastrointestinal, urogenital and respiratory tracts. These internal surfaces act as a barrier to the outside world for the internal tissues of the body, which are then further protected by the systemic immune system.

There is some convincing evidence that probiotics, or gut-friendly bacteria, influence the development and maintenance not only of the microbial balance inside the gut and the mucosal immune system but also the systemic immune response.

The name of the probiotic in this new study is Bifidobacterium infantis 35624, which was discovered in the early 1990s by microbiologists at Alimentary Health, a development biotech based in Cork, Ireland, in partnership with Procter and Gamble.

The gut-friendly bacterium is the main ingredient in Procter & Gamble’s Align dietary supplement which is commercially available in the US.

The new study, which was conducted by scientists from Alimentary Health and the Alimentary Pharmabiotic Centre at University College Cork, includes three separate randomized, double-blind placebo-controlled trials of the effect of the probiotic in both gastrointestinal and non-gastrointestinal related disorders.

For the trials, the team recruited 22 patients with the gastrointestinal disorder ulcerative colitis (UC), 26 patients with the inflammatory skin condition psoriasis, and a further 48 patients with chronic fatigue syndrome (CFS), another inflammatory disease.

There was also a group of 35 healthy volunteers. These were used as baseline references for levels of inflammation markers in the patients and some went on to take part in the trial itself.