International travel disrupts gut health through dietary changes, microbial exposure, and stress, often causing gastrointestinal symptoms like traveler's diarrhea and sleep disturbances. These shifts may increase antibiotic resistance risks. Probiotics may help stabilize gut microbiota and improve well-being during travel. This randomized, double-blind, placebo-controlled trial investigated whether probiotic supplementation mitigates gut microbiota perturbations, gastrointestinal symptoms, and sleep issues in adults traveling abroad. The investigators also assessed changes in anxiety, well-being, gut immunity, microbial function, and antibiotic resistance genes.