Efficacy of a prebiotic formulation for treatment of functional constipation and associated gastrointestinal symptoms in adults: A randomised controlled trial

Functional constipation is the result of a complex interplay between the gastrointestinal tract, the gut microbiome, the nervous system, along with diet and lifestyle factors. This study aimed to evaluate the efficacy of a prebiotic formulation containing plant-based extracts rich in dietary fibre and polyphenols in the management of functional constipation and associated gastrointestinal symptoms. This 3-week randomised controlled study assessed the effect of a prebiotic formulation (6 g powder taken in water twice daily), by comparison with a capsule designed to have minimal effect on gastrointestinal function, on indicators of bowel health in healthy adults with low fibre intake and meeting the Rome IV criteria for functional constipation. Participants were informed that they may receive one of two products, either a powder or a capsule, both of which contained prebiotics. The primary outcome was change in frequency of complete spontaneous bowel movements. Secondary outcomes assessed were gastrointestinal symptoms, quality of life and mood using the PAC-SYM, PAC-QoL, and DASS-21. Safety and tolerability were also assessed. Results: There was a significant improvement in bowel movements (p < 0.001) and improved stool consistency (p < 0.01) in participants taking the prebiotic powder formulation compared to those taking the capsule. Accompanying this was a significant reduction in overall gastrointestinal symptoms (p < 0.001) including abdominal (p < 0.001), rectal (p = 0.004) and stool (p = 0.002) symptoms, and a significant improvement in quality of life (p < 0.001). There was a significant reduction in mean score for depression, anxiety, and stress for participants in both groups, which indicated a significant improvement in mood during the study that was unrelated to bowel function. The results showed that the prebiotic powder formulation taken twice per day for 21 days was effective in reducing clinical symptoms of functional constipation in individuals reporting a low fibre intake.