Effects of psyllium vs. placebo on constipation, weight, glycemia, and lipids: A randomized trial in patients with type 2 diabetes and chronic constipation.

Objective: To compare the effects of baked psyllium supplementation versus those who received a placebo on constipation symptoms, body weight, glycemic and lipids control in patients with type 2 diabetes (T2D) and chronic constipation.

Methods: In a single-blinded, randomized controlled trial, 51 patients with T2D and chronic constipation with body mass index (BMI) 20-47 kg/m received either 10 g of psyllium pre-mixed in cookies twice per day or placebo cookies for 12 weeks. Constipation symptoms, body mass index (BMI), fasting plasma glucose (FPG), glycosylated hemoglobin (HbA1c), and lipid profile were determined at the beginning and end of 4, 8, and 12-week period. Constipation was evaluated with a stool diary (ROME III).

Results: The psyllium group showed improvement in constipation symptoms, body weight, glucose and lipid values compared with the baseline and the placebo group. Body weight and FPG decreased from baseline in the psyllium group (P < 0.001 and P = 0.056, respectively). The differences (95% CI) of absolute change of body weight (-2.0 (-3.0, -1.0) kg; P < 0.001), FPG (-13.6 (-24.3, -2.9) mg/dl; P = .040), and HbA1c (-1.7 (-2.9, -0.5)); P = 0.002) between the groups were statistically significant. Cholesterol (-21.5 (-25.6, -14.4); P < 0.001), triglycerides (-20.0 (-32.3, -7.7); P = 0.021) and constipation symptoms (1.5 (0.4, 2.3); P < 0.001) decreased in the psyllium group. The compliance was good and no adverse effects were observed.

Conclusion: In patients with T2D and chronic constipation, psyllium supplementation decreased constipation symptoms, body weight, glycemic, cholesterol, and increased HDLC levels.