Conducted by researchers from AB-Biotics, Spain (a subsidiary of Kaneka Probiotics), supplements startup 3 Waves Wellness and the contract research organization Wasatch Scientific, in the US, the findings demonstrate the potential of the ‘psychobiotic’ strain to impact a wider range of health areas.
“Research on the gut-brain-axis has traditionally focused on cognition and mood, but research has shown that these pathways also play a key role in metabolic health, such as weight management and energy,” said Miquel Angel Bonachera, executive director and co-founder at AB-Biotics. “We wanted to explore how well KABP 051 could positively influence both emotional wellbeing and body composition through this interconnected gut brain and metabolism axis.”
Published in the Journal of Medicinal Food, the study recruited 60 healthy overweight adults (BMI 25–35) with moderate stress levels who were instructed to take either L. plantarum KABP-051 (1 billion CFU/day) or placebo daily for 12 weeks.
Resulting data indicated the probiotic group experienced greater improvements in body composition measurements compared to placebo, with an average 1.26% greater decrease in body fat percentage and 2.4% greater decrease in body weight.
While modest, body weight reductions of this size are associated with meaningful health benefits, including improvements in cardiovascular risk factors and glycemic control, according to Bonachera.
Further, mood assessments revealed greater reductions in fatigue and confusion in the probiotic group after 12 weeks, compared to placebo.
“Body weight and mental wellbeing are deeply interconnected, and both are strongly influenced by the gut microbiome,” said Bonachera. “This research demonstrates how these connections can be harnessed to deliver meaningful improvements in both body composition and mood with a single intervention like L. plantarum KABP-051.
“For many consumers, weight management is as much about feeling more energized and mentally well as it is about the physical outcomes.”
He suggested that by improving mood and energy levels through the gut–brain axis, L. plantarum KABP-051 may have enabled better self-regulation, supporting long-term adherence to healthier habits.
“These are exciting results that point toward next generation probiotic solutions with the potential to transform how we support consumers on their weight management and healthy lifestyle journeys.”
Body composition improvements in overweight participants
The randomized, placebo-controlled, double-blind study recruited 60 healthy but overweight or obese (BMI of 25–35 and body fat percentage of 20–30%) participants, aged 18 to 65, who were moderately stressed (measured using Perceived Stress Scale PSS-10).
Volunteers were randomly allocated to receive either L. plantarum KABP051 (1 billion cfu) or matching placebo (microcrystalline cellulose, both supplied by Kaneka) for 90 days.
Subjects also participated in weekly (via online webinar) lifestyle education sessions on nutrition, exercise, sleep, stress, and related healthy lifestyle topics, including a diet, exercise and sleep regimen.
The primary study endpoints were body weight, waist circumference, and body fat (measured using InBody 770 machine). Changes in mood, focus, and energy were assessed using the Profile of Mood States (POMS) questionnaire to measure six primary psychological factors (tension, mood, irritability, fatigue, confusion, and vigor) plus the combined global mood state (total mood disturbance, TMD) as an indication of overall subjective well-being.
For salivary cortisol analysis, participants were provided with an at-home saliva collection kit with instructions to collect a morning saliva sample before eating or brushing their teeth.
Microbiome PCR analysis of fecal samples was performed using the complete BiomeTracker system (Wasatch Scientific).
Improved body fat and mood
At week 12, the placebo group had a mean body weight increase of 0.27kg, compared with the probiotic group which showed a mean decrease of 1.68 kg.
The placebo group had a mean waist circumference reduction of 0.21 cm, compared to a reduction of 3.36 cm in the probiotic group. And the placebo group had a 0.35% increase in body fat, compared with a 0.91% decrease in the probiotic group.
In post-hoc analyses, change at 12 weeks was significant for all three parameters (P = .014, P = .011, and P = .025, respectively), compared with placebo.
Regarding mood status, a global trend was observed in fatigue (P = .096) and confusion sub-scores (P = .095) compared with placebo, with significant changes at 12 weeks for both parameters (P = .014 and P = .016, respectively) in post-hoc analysis. Conversely, the other sub-scores and the overall TMD score did not show relevant changes.
Salivary cortisol levels indicated the placebo group showed a 12% increase from baseline concentration, while the probiotic group exhibited a 16% decrease. The between-group difference was not statistically significant.
Among the bacterial components of the microbiota, global significant changes were observed for Lactobacillus spp. but no differences were found between KABP051 and placebo in the Bacteroidetes, Firmicutes, Bifidobacterium spp., and Akkermansia spp. bacterial groups.
“Further investigations in larger populations are warranted to fully elucidate the underlying mechanisms by which L. plantarumKABP051 may exert their metabolic and psychobiotic effects," the report stated.
Source: Journal of Medicinal Food, https://doi.org/10.1177/1096620X26144804 “Effects of Lactiplantibacillus Plantarum KABP051 Probiotic on Body Composition, Microbiome and Mood in Healthy Overweight Adults“. Authors: Talbott, S., et al
