Efficacy of Bifidobacterium animalis subspecies lactis CECT 8145 probiotic, delivered in a chewing gum, on abdominal fat distribution and cardiometabolic biomarkers in adults with abdominal obesity: a randomized triple-blind parallel controlled trial

Background and aims Abdominal obesity is associated with cardiometabolic disease (CMD). While probiotics have shown potential metabolic benefits, their effect on abdominal fat distribution remains unclear. Therefore, the aim of this study is to evaluate the efficacy of Bifidobacterium animalis subsp. lactis CECT 8145 probiotic (Ba8145), delivered via sugar-free chewing gum, on abdominal fat distribution and CMD biomarkers in adults with abdominal obesity. Methods A 12-week, randomized, triple-blind, parallel, placebo-controlled clinical trial with 1:1 allocation into: (1) Ba8145 probiotic chewing gum (1×10 10 CFU/day) and (2) placebo chewing gum. Results A total of 113 participants received an intervention (probiotic group n = 53/113; mean age 53.6 ± 11.0 years; 67.26% women). At 12 weeks, no significant inter-group differences were observed for waist circumference measured by MRI. Nonetheless, Ba8145 significantly decreased VAT/SAT ratio (thickness) by MRI [−0.305 (−0.57; −0.04), p = 0.022] and conicity index [−0.013 (−0.03; −0.011), p = 0.037], versus placebo. Hunger scores significantly decreased in Ba8145versus placebo. In men, inter-group analyses showed a significant decrease in intra-abdominal area by MRI [−16.9 cm 2 (−33; −0.90), p = 0.039], VAT thickness by US [−0.665 cm (−1.3; −0.05), p = 0.034], VAT/SAT ratio (thickness) by US [−0.077 (−0.13; −0.02), p = 0.007], VAT/SAT ratio (thickness) by MRI [−0.425 (−0.78; −0.07), p = 0.022], and conicity index [−0.022 (−0.04; −0.002), p = 0.035], in favor of Ba8145. Additionally, Ba8145 significantly decreased total cholesterol, LDL-c, ApoA1, ApoB, and in men, non-esterified fatty acids (NEFA), and serum IL-6 versus placebo. Changes in the VAT/SAT ratio (thickness) by US and MRI were correlated with changes in serum NEFA in all population and men. Conclusion Ba8145 probiotic via sugar-free chewing gum improved abdominal fat distribution, total cholesterol and hunger scores in the overall population, without significant changes in waist circumference measured by MRI. Additional improvements in visceral adiposity and CMD biomarkers were observed in men. These results support Ba8145 as a promising, safe, and complementary approach for managing metabolic health warranting further investigation. Clinical trial registration Registered on ClinicalTrials.gov (NCT05882149).