Abstract
BACKGROUND: Evidence of probiotics effects on gut function, brain activity and emotional behaviour were provided. Probiotics can have dramatic effects on behaviour through the microbiome-gut-brain axis, through vagus nerve. We investigated whether chronic probiotic intake could modulate psychological state, eating behaviour and body composition of normal weight obese (NWO) and preobese-obese (PreOB/OB) compared to normal weight lean women (NWL). METHODS: 60 women were enrolled. At baseline and after a 3-week probiotic oral suspension (POS) intake, all subjects underwent evaluation of body composition by anthropometry and dual X-ray absorptiometry, and psychological profile assessment by self-report questionnaires (i.e. EDI-2, SCL90R and BUT). Statistical analysis was carried out using paired t test or a non-parametric Wilcoxon test to evaluate differences between baseline and after POS intake, one-way ANOVA to compare all three groups and, where applicable, Chi square or t test were used to assess symptoms. RESULTS: Of the 48 women that concluded the study, 24% were NWO, 26% were NWL and 50% were PreOB/OB. Significant differences in body composition were highlighted among groups both at baseline and after a POS (p < 0.05). After POS intake, a significant reduction of BMI, resistance, FM (kg and %) (p < 0.05), and a significant increase of FFM (kg and %) (p < 0.05) were observed in all subjects in NOW and PreOB/OB. After POS intake, reduction of bacterial overgrowth syndrome (p < 0.05) and lower psychopathological scores (p < 0.05) were observed in NWO and PreOB/OB women. At baseline and after POS intake, all subjects tested were negative to SCL90R_GSI scale, but after treatment subjects positive to BUT_GSI scale were significantly reduced (8.33%) (p < 0.05) compared to the baseline (33.30%). In NWO and PreOB/OB groups significant differences (p < 0.05) in response to the subscales of the EDI-2 were observed. Significant improvement of the orocecal transit time was observed (p < 0.05) after POS intake. Furthermore, significant differences were observed for meteorism (p < 0.05) and defecation frequency (p < 0.05). CONCLUSIONS: A 3-week intake of selected psychobiotics modulated body composition, bacterial contamination, psychopathological scores of NWO and PreOB/OB women. Further research is needed on a larger population and for a longer period of treatment before definitive conclusions can be made. Trial registration ClinicalTrials.gov Id: NCT01890070.