Across 5 review studies, all 5 reported beneficial effects of Lactobacillus salivarius UCC118 on immune function, with predominantly small effect sizes. Doses, study durations, and specific populations were not consistently reported, limiting the precision of the finding. The evidence is drawn entirely from narrative reviews, with no statistically significant findings or original clinical trials included.
Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). The evidence base is small (only 5 studies), and all are reviews rather than original clinical trials — conclusions should be considered preliminary. Many of the included studies did not reach statistical significance — effect may be smaller than the predominant direction suggests. Doses, forms, and study durations were not reported, preventing any dose-response or form-specific conclusions.
strengthen the immune system
another critical role of bacteriocins is their immunomodulatory effect
Lactobacilli comprise an important group of probiotics... [their components] mediate positive effect on the host, such as immunomodulatory... effects.
low- and moderate-intensity exercise has been shown to reduce physiological stress and improve immune function
stimulate/modulate of the immune system