A Randomized Controlled Trial Evaluating the Effects of a Probiotic Containing Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 on Gastrointestinal Symptoms and Metabolomic Profiles in Female Dancers

Dancers experience physical and psychological stressors that can impact gut health. We hypothesized that a three-month supplementation with <i>Lactobacillus helveticus</i> R0052 and <i>Bifidobacterium longum</i> R0175 would result in measurable alterations in the fecal metabolomic profile and improve gastrointestinal symptomatology in dancers. Of the 51 volunteers, 26 female dancers were randomized to a 12-week trial (NCT05567653). A homogenous group of 16 (probiotic: <i>n</i> = 5; placebo: <i>n</i> = 11) was analyzed. The participants received <i>L. helveticus</i> R0052 and <i>B. longum</i> R0175 (3 × 10⁹ colony-forming units/day) or a placebo. Baseline dietary intake and body composition were recorded. Fecal samples were analyzed using liquid chromatography-mass spectrometry, and gastrointestinal symptoms were assessed with the Rome IV questionnaire. Statistical methods included principal component analysis, mixed-effects models, and analysis of variance-simultaneous component analysis (ASCA). The study revealed shifts in the probiotic group's fecal metabolome (permutation test <i>p</i> = 0.026), including a reduction in (2RS)-2-(4-hydroxyphenyl)propionic acid (<i>p</i> = 0.023). No improvement in gastrointestinal symptoms was observed. No adverse events occurred. <i>L. helveticus</i> R0052 and <i>B. longum</i> R0175 may alter the gut metabolome, notably (2RS)-2-(4-hydroxyphenyl)propionic acid, but small sample size and absent symptom improvement limit the conclusions. Larger studies with varied doses and blood metabolite analysis are needed to confirm relevance.