Efficacy of soluble fiber supplementation in CVD risk management of patients affected by metabolic syndrome: A 6-months, open-label, RCT

Background: Increasing dietary soluble fibers is recommended as a safe and practical approach for cholesterol reduction. Aim: To comparatively evaluate the long-term effect of the psyllium husk and guar gum supplementation on metabolic syndrome (MS) components. Methods: 141 consecutively enrolled MS patients were randomized to soluble psyllium husk powder or partially hydrolyzed guar gum 3.5 gr t.i.d. and to be taken 20’ before the main 2 meals, or to standard diet for 6 months. Results: Both fibers improved significantly BMI (-2.9% vs. –3.3%), FPG (-16.4% vs. –9.3%), and LDL-C (-4.4% vs –4.3%) after 4 months of treatment, and a broader range of metabolic parameters after 6 months: BMI (-7.2% vs. –6.5%), FPG (-27.9% vs. –11.1%), FPI (-20.4% vs. –10.8%), HOMA Index (-39.2% vs. –16.7%), HbA1c (-10.4% vs. –10.3%), LDL-C (-7.9% vs. –8.5%) and ApoB (-10.5% vs. –5.6%). Only the 6 months psyllium supplementation exerted a significant improvement in plasma TG concentration (-13.3%) and in SBP (-3.9%) and DBP (-2.6%). At the end of the study, the 12.5% of patients in the psyllium group did not comply to the criteria for the diagnosis of MS compared with only the 2.1% in the guar group. No significant difference has been observed as it regards the standard diet group in comparison to the baseline. Conclusions: Psyllium could be more indicated for patients that have to reduce a large number of CV risk factors, while guar gum could be more rapidly efficacious in strengthening the effect of diets aimed at reducing body weight.