Fiber intake and glycemic control in patients with type 2 diabetes mellitus: a systematic review with meta-analysis of randomized controlled trials

Nutr Rev. 2013 Dec;71(12):790-801. doi: 10.1111/nure.12076. Epub 2013 Nov 1.


This systematic review with meta-analysis of randomized controlled trials (RCT) aimed to analyze the effect of fiber intake on glycemic control in patients with type 2 diabetes. Databases were searched up to November 2012 using the following medical subject headings: diabetes, fiber, and randomized controlled trial. Absolute changes in glycated hemoglobin and fasting plasma glucose were reported as differences between baseline and end-of-study measures. Pooled estimates were obtained using random-effects models. Of the 22,046 articles initially identified, 11 (13 comparisons; range of duration, 8-24 weeks) fulfilled the inclusion criteria, providing data from 605 patients. High-fiber diets, including diets with foods rich in fiber (up to 42.5 g/day; four studies) or supplements containing soluble fiber (up to 15.0 g/day; nine studies), reduced absolute values of glycated hemoglobin by 0.55% (95% CI -0.96 to -0.13) and fasting plasma glucose by 9.97 mg/dL (95% CI -18.16 to -1.78). In conclusion, increased fiber intake improved glycemic control, indicating it should be considered as an adjunctive tool in the treatment of patients with type 2 diabetes.

Keywords: dietary fiber; glycated hemoglobin; meta-analysis; type 2 diabetes mellitus.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Blood Glucose / metabolism*
  • Diabetes Mellitus, Type 2 / metabolism*
  • Dietary Fiber / administration & dosage*
  • Dietary Fiber / pharmacology
  • Glycated Hemoglobin A / metabolism
  • Humans
  • Randomized Controlled Trials as Topic


  • Blood Glucose
  • Dietary Fiber
  • Glycated Hemoglobin A