Introduction <p>Obesity is a complex health condition marked by an excessive accumulation of adipose tissue. Bariatric surgery continues to be the most efficacious intervention for attaining significant and enduring weight loss. This study aimed to assess a 6-month probiotics supplementation effect on quality of life (QoL), bowel habits, excess weight loss (EWL) and changes in stool composition and fecal Calprotectin in severely obese patients undergoing different types of bariatric surgeries.</p> Methods <p>This prospective randomized controlled trial involved 200 cases underwent standardized bariatric procedures. Cases were randomized into two equal groups: Probiotic group received either Enterogermina^® 6&#xa0;billion sachets or Lacteol forte^® sachets, one sachet twice daily for 6 months postoperatively and control group: Patients received standard postoperative care without probiotics.</p> Results <p>At 1 month postoperatively, the probiotics group showed a significantly higher QOL and EWL% (<i>p</i> &lt; 0.001) compared to controls. At 3 months, the probiotics group had a significantly higher QOL and EWL% (<i>p</i> &lt; 0.001). At 6 months, the probiotics group showed a statistically significant improvements across all measured outcomes, including QOL, BHQ, and EWL% compared to the control group(<i>p</i> &lt; 0.001). Probiotic group had a significantly lower fecal calprotectin compared to control group (<i>p</i> &lt; 0.001).</p> Conclusion <p>The probiotic use post-bariatric surgery offers measurable benefits in QOL, weight loss, and gastrointestinal inflammation, regardless of the surgical type. Although procedures like RYGB and OAGB yield superior weight loss, they may induce higher gut inflammation. Meanwhile, sleeve gastrectomy appears to be the most gut-friendly in terms of inflammatory markers and bowel consistency.</p>