Soluble dietary fiber (DF) reduces the risk of developing diabetes and may have therapeutic effects in patients with type 2 diabetes mellitus (DM2). The present study aimed to investigate the effect of soluble DF on metabolic control in patients with DM2. A total of 117 patients with DM2 between the ages of 40 and 70 were assessed. Patients were randomly assigned to one of two groups, and administered extra soluble DF (10 or 20 g/day), or to a control group (0 g/day) for one month. Blood glucose, serum insulin and connecting peptide (C-peptide) levels, and the insulin resistance index, as determined using the homeostatic model assessment method, were measured during fasting and up to 2-h postprandially prior to and following one month of treatment. Other measurements included serum levels of glycated albumin (GA), blood lipid profiles, and an analysis of the blood pressure, body weight and waist/hip ratio of all patients. Following intervention, the levels of 2-h blood glucose, fasting insulin and lipoprotein(a), and the insulin resistance index, were significantly improved in all groups. Furthermore, the fasting blood glucose, 2-h insulin, fasting C-peptide, 2-h C-peptide, GA and triglyceride (TG) levels were significantly improved in the soluble DF groups. The 20 g/day soluble DF group exhibited significantly improved fasting blood glucose and low-density lipoprotein levels, as well as a significantly improved insulin resistance index. In addition, 10 and 20 g/day soluble DF significantly improved the waist and hip circumferences and levels of TGs and apolipoprotein A. The results of the present study suggested that increased and regular consumption of soluble DF led to significant improvements in blood glucose levels, insulin resistance and metabolic profiles, without improving the secretory function of the islets of Langerhans, over a short-term intervention period in patients with DM2.
Keywords: blood glucose; glycated albumin; insulin resistance index; soluble dietary fiber; type 2 diabetes mellitus.