Dietary Glycemic Index and Load and the Risk of Type 2 Diabetes: A Systematic Review and Updated Meta-Analyses of Prospective Cohort Studies

Nutrients. 2019 Jun 5;11(6):1280. doi: 10.3390/nu11061280.


Published meta-analyses indicate significant but inconsistent incident type-2 diabetes(T2D)-dietary glycemic index (GI) and glycemic load (GL) risk ratios or risk relations (RR). It is nowover a decade ago that a published meta-analysis used a predefined standard to identify validstudies. Considering valid studies only, and using random effects dose-response meta-analysis(DRM) while withdrawing spurious results (p < 0.05), we ascertained whether these relationswould support nutrition guidance, specifically for an RR > 1.20 with a lower 95% confidence limit>1.10 across typical intakes (approximately 10th to 90th percentiles of population intakes). Thecombined T2D-GI RR was 1.27 (1.15-1.40) (p < 0.001, n = 10 studies) per 10 units GI, while that forthe T2D-GL RR was 1.26 (1.15-1.37) (p < 0.001, n = 15) per 80 g/d GL in a 2000 kcal (8400 kJ) diet.The corresponding global DRM using restricted cubic splines were 1.87 (1.56-2.25) (p < 0.001, n =10) and 1.89 (1.66-2.16) (p < 0.001, n = 15) from 47.6 to 76.1 units GI and 73 to 257 g/d GL in a 2000kcal diet, respectively. In conclusion, among adults initially in good health, diets higher in GI or GLwere robustly associated with incident T2D. Together with mechanistic and other data, thissupports that consideration should be given to these dietary risk factors in nutrition advice.Concerning the public health relevance at the global level, our evidence indicates that GI and GLare substantial food markers predicting the development of T2D worldwide, for persons ofEuropean ancestry and of East Asian ancestry.

Keywords: alcohol; cohort studies; dietary fiber; epidemiology; glycemic index; glycemic load; meta-analysis; protein; type 2 diabetes.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Adult
  • Blood Glucose / analysis*
  • Diabetes Mellitus, Type 2 / etiology*
  • Diet / adverse effects*
  • Dietary Carbohydrates / adverse effects
  • Female
  • Glycemic Index*
  • Glycemic Load*
  • Humans
  • Male
  • Middle Aged
  • Odds Ratio
  • Prospective Studies
  • Risk Factors


  • Blood Glucose
  • Dietary Carbohydrates