Dietary Glycemic Index, Glycemic Load, and Digestible Carbohydrate Intake Are Not Associated with Risk of Type 2 Diabetes in Eight European Countries

Abstract

The association of glycemic index (GI) and glycemic load (GL) with the risk of type 2 diabetes remains unclear. We investigated associations of dietary GI, GL, and digestible carbohydrate with incident type 2 diabetes. We performed a case-cohort study nested within the European Prospective Investigation into Cancer and Nutrition Study, including a random subcohort (n = 16,835) and incident type 2 diabetes cases (n = 12,403). The median follow-up time was 12 y. Baseline dietary intakes were assessed using country-specific dietary questionnaires. Country-specific HR were calculated and pooled using random effects meta-analysis. Dietary GI, GL, and digestible carbohydrate in the subcohort were (mean ± SD) 56 ± 4, 127 ± 23, and 226 ± 36 g/d, respectively. After adjustment for confounders, GI and GL were not associated with incident diabetes [HR highest vs. lowest quartile (HR(Q4)) for GI: 1.05 (95% CI = 0.96, 1.16); HR(Q4) for GL: 1.07 (95% CI = 0.95, 1.20)]. Digestible carbohydrate intake was not associated with incident diabetes [HR(Q4): 0.98 (95% CI = 0.86, 1.10)]. In additional analyses, we found that discrepancies in the GI value assignment to foods possibly explain differences in GI associations with diabetes within the same study population. In conclusion, an expansion of the GI tables and systematic GI value assignment to foods may be needed to improve the validity of GI values derived in such studies, after which GI associations may need reevaluation. Our study shows that digestible carbohydrate intake is not associated with diabetes risk and suggests that diabetes risk with high-GI and -GL diets may be more modest than initial studies suggested.

Glycemic Index of Some Traditional Fruits in Jamaica

“…Glycemic load (GL) investigates the total impact of the dietary carbohydrate on blood glucose level after meal. The GL of a serving of food is the mathematical product of the amount of available carbohydrate (g) in that serving and the glycemic index of the food divided by 100 [3,[11][12][13]. The higher the GL of the food, the greater the rise of blood glucose and insulin levels.…”

A High Dietary Glycemic Index Increases Total Mortality in a Mediterranean Population at High Cardiovascular Risk

“…Recent meta-analyses have shown a relationship between dietary GI, GL and increased risk of CVD in women but not in men [35], [38], [39], greater risk of T2DM [6], [40], [41], and risk for certain types of cancer such as colorectal or endometrial ones [11], [42]. Higher dietary GI has also been associated with an increased risk of breast cancer [6], [11], [43] although these results are contradictory [44]–[46].…”

Long‐term Low‐carbohydrate Diets and Type 2 Diabetes Risk: A Systematic Review and Meta‐analysis of Observational Studies

“…Nine articles [17][18][19][20][21][22][23][24][25] were excluded from the systematic review because of overlapping populations. Out of these 22 articles, a total of 13 cohort studies [26][27][28][29][30][31][32][33][34][35][36][37][38] were appraised in the systematic review and metaanalysis. The 13 selected articles included in the systematic review were moderately heterogeneous in terms of population demographics, carbohydrate intake parameters, and the assessment of confounding factors.…”

“…The follow-up rate was more than 90% in most of the studies. Carbohydrate intake was assessed using the residual method in 5 studies 30,34,35,37,38 and by the density method in 3 studies. [31][32][33] The method was not specified in the remaining reports.…”