Obesity and mental health disorders are among the greatest public health challenges of the twenty-first century. Interestingly, an altered microbiome profile has been associated with both conditions. The aim of this randomized, double-blind, placebo-controlled clinical trial was to evaluate the effects of dietary supplementation with a specific probiotic strain (Lactiplantibacillus plantarum KABP051) on body composition and gut microbiome balance, together with measures of mood state, in a population of healthy overweight subjects. Sixty healthy, moderately stressed, non-depressed and overweight or obese volunteers were supplemented for 12 weeks with probiotic (L. plantarum KABP051; 1 billion cfu/day) or placebo (microcrystalline cellulose). The KABP051 group experienced significantly greater improvements compared to placebo on body composition measurements, including a reduction in body weight and waist circumference, which decreased in 1.97±0.77 (mean±SE) kg and 2.15±0.81 (mean±SE) cm vs. placebo at the end of the intervention (both p< 0.05, MMRM and post-hoc analysis). Microbiome composition improved in KABP051 group, with significant increase in the relative abundance of Lactiplantibacillus spp. vs. placebo. Body fat percentage, POMS fatigue, and confusion sub-scores showed a global trend toward improvement compared to placebo, with the change at 12 weeks being significant in the three measurements in post-hoc analysis (p=0.015, p=0.014 and p=0.016, respectively). No serious adverse events were registered during the intervention period. These results suggest that a specific strain of probiotic bacteria (L. plantarum KABP051) may have both metabolic and psychobiotic effects and may be beneficial for enhancing weight loss and body composition, improving energy and mood levels while embarking on a healthy lifestyle regimen.

ST and JT are employees of 3Waves Wellness, a contract research organization that was compensated for designing and conducting this trial. AF is an employee of Kaneka/AB-Biotics, the producer of the probiotic strain used in this study.

NCT06808061

Kaneka/AB-Biotics provided the probiotic dietary supplements and funded the costs associated with microbiome assessments and psychological surveys.

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