Brown rice bran powder, when added to the standard diet, could alleviate cardiometabolic risk factors and antioxidant status in patients with metabolic syndrome

Introduction Due to its beneficial contents including dietary fiber and γ-oryzanol, brown rice bran powder (BRBP) can be considered as a functional food item. Hence, the current trial aims to investigate the effects of BRBP consumption on cardiometabolic risk factors, antioxidant status, and gastrointestinal symptoms in adults diagnosed with metabolic syndrome (MetSyn).

Subjects, Materials and Methods In this 8-week open label, controlled trial, fifty patients with MetSyn were randomized into a control (who only received the standard diet (SDiet)), or intervention group (who were additionally administered 15g/day BRBP). Patients’ demographic and anthropometric data were recorded. Blood samples were then gathered to analyze levels of metabolic factors and antioxidant enzymes activity. Moreover, the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire was completed.

Results Analysis of covariance (ANCOVA) controlled for the baseline levels revealed that at the study endpoint, compared to the controls who only followed a SDiet, patients who additionally received BRBP showed significant reductions in body mass index (BMI) and (P-value<0.0001; effect size (ES): -1.29), waist circumference (P-value<0.001; ES: -1.12), total-cholesterol (P-value=0.046; ES: -0.66), low-density lipoprotein-cholesterol (P-value=0.037; ES: -0.67), fasting blood sugar (P-value=0.015; ES: -0.79). Further, BRBP consumption resulted in significant improvements in high-density lipoprotein-cholesterol (P-value=0.050; ES: 0.62), serum activities of catalase (P-value=0.026; ES: 0.72), glutathione peroxidase (P-value<0.001; ES: 1.08), and superoxide dismutase (P-value=0.009; ES: 0.84), as well as constipation rate (P-value=0.018; ES: -0.85) compared to SDiet alone. However, no significant changes were found regarding levels of triglyceride, glutathione, and blood pressure after the trial.

Conclusion The findings of this trial support the weight-reducing, hypocholestrolemic, ant-hyperglycemic, and antioxidative effects of adding BRBP to SDiet prescribing for MetSyn patients.