A new study published in the Journal of Medicinal Food evaluated the effects of reduced form coenzyme Q 10 (ubiquinol) intake on defecation frequency and stool form in patients with daily abdominal symptoms. This was a single-center, prospective, double-blinded, randomized controlled trial, which enrolled 41 patients with daily symptom of either constipation or diarrhea. Patients were assigned to receive either ubiquinol (150 mg/day) or placebo for 12 weeks. A daily record of number of defecations and stool forms, according to the Bristol Stool Form (BSF) Scale for 7 days at baseline and 12 weeks, were maintained. Quality of life (QOL) was assessed using the 36-item short-form (SF-36) at baseline and 12 weeks. The findings showed that at 12 weeks, the mean defecation frequency significantly decreased compared to baseline in the ubiquinol group and increased in the placebo group. There was no significant change in the 12-week BSF Scale score of the ubiquinol group, whereas that of the placebo group had increased. Furthermore, the 12-week general health perception SF-36 score was significantly increased in the ubiquinol group, whereas there was no significant difference in SF-36 score in the placebo group. Hence, it was concluded that taking ubiquinol for 12 weeks decreased defecation frequencies and increased the QOL score, suggesting that ubiquinol may change bowel habits and improve QOL in patients with abdominal distress.