Prebiotic fiber plus probiotics shows immune-boosting effects in healthy adults

06-May-2014 - Last updated on 07-May-2014 at 13:30 GMT

"It may be advantageous to provide XOS as a synbiotic with Bi-07 to simultaneously derive the benefits observed with Bi-07 supplementation while optimizing product acceptability"

Daily supplements of xylo-oligosaccharide prebiotic fibers with probiotics may modulate immune function in healthy adults, says new study.

Eight grams of the xylo-oligosaccharide prebiotic (XOS, Shandong Long-live Biotech) per day for three weeks was found to increase vitality and happiness scores, and when used in combination with Bifidobacterium animalis subsp. lactis Bi-07 (Danisco) the researchers found a reduction in the use of analgesics

Prebiotics are "non-digestible substances that provide a beneficial physiological effect on the host by selectively stimulating the favorable growth or activity of a limited number of indigenous bacteria". According the FAO/WHO, probiotics are defined as "live microorganisms which when administered in adequate amounts confer a health benefit on the host". Synbiotics are a combination of the two.

The effects of the prebiotic and probiotic observed in the new study appear to be additive and not synergistic, wrote researchers from the University of Reading (UK), the University of Southampton (UK), DuPont Nutrition and Health (Finland), and the University of Turku (Finland) in the British Journal of Nutrition.

“It may be advantageous to provide XOS as a synbiotic with Bi-07 to simultaneously derive the benefits observed with Bi-07 supplementation while optimizing product acceptability, as solubility, in particular, was poor when Bi-07 was provided alone,” they wrote. “Therefore, this synbiotic preparation is recommended due to additive effects rather than due to specific synergistic effects.”

Study details

Dr Caroline Childs from the University of Southampton and her co-authors report that they recruited 44 healthy adults aged between 25 and 65 to participate in their placebo-controlled cross-over study. Participants were randomly assigned to receive placebo (maltodextrin), probiotic plus placebo, prebiotic plus placebo, or probiotic plus prebiotic for 21 days. Interventions were separated by a 28 washout period before crossing over to other interventions.

Results for the 41 people who completed the trial indicated that the XOS prebiotic-only intervention boosted the number of bowel movements per day, but did not produce any adverse effects such as bloating, abdominal pain or flatulence. Participant-reported vitality and happiness were also significantly improved on XOS supplementation.

Immune effects

The supplements were found to influence immune responses from T lymphocytes for both Th1 and Th2. The former is the response for perpetuating autoimmune responses. T-helper type 2 (Th2) lymphocytes, on the other hand, are associated with allergic response, and produce protein-like cytokines, such as interleukin-4 (IL-4), IL-5 and IL-6, which in turn promote the synthesis of the immune chemicals immunoglobulins (Ig) to bind to the allergens.

Indeed, IL-4 secretion in the probiotic group was reduced, as was IgA content in the saliva. XOS supplementation was associated with lower expression of changes in the cell-surface markers on natural killer T-cells.

“[T]hese effects suggest that XOS and Bi-07 have immunostimulatory effects, promoting Th1 responses and lowering Th2 activity,” wrote the researchers.

“Therefore, these effects may be of benefit to individuals with suppressed Th1 activity, e.g. the elderly, or those with excessive Th2 activity, such as that occurring in atopic disease.”

“The functional consequences of these changes in the measures of immune function should be investigated in suitably designed human studies, preferably using in vivo markers of immune function, such as the incidence of allergic rhinitis symptoms or influenza vaccination responses,” they concluded.

Source: British Journal of Nutrition
Published online ahead of print, FirstView Article doi: 10.1017/S0007114513004261
“Xylo-oligosaccharides alone or in synbiotic combination with Bifidobacterium animalis subsp. lactis induce bifidogenesis and modulate markers of immune function in healthy adults: a double-blind, placebo-controlled, randomised, factorial cross-over study”
Authors: Childs CE, Roytio H, Alhoniemi E, Fekete AA, Forssten SD, Hudjec N, Lim YN, Steger CJ, Yaqoob P, Tuohy KM, Rastall RA, Ouwehand AC, Gibson GR.