(HealthDay News) — Low glycemic index (GI)/glycemic load (GL) dietary patterns are associated with a reduction of hemoglobin A1c (HbA1c) in adults with type 1 and 2 diabetes, according to a review published online Aug. 4 in The BMJ.
Laura Chiavaroli, Ph.D., from the University of Toronto, and colleagues conducted a systematic review and meta-analysis of randomized controlled trials that examined the effect of diets with low GI or GL in diabetes. Twenty-nine trial comparisons were identified in 1,617 participants with type 1 and 2 diabetes, who were mainly middle-aged, overweight or obese, and had moderately controlled type 2 diabetes.
The researchers found that compared with higher GI/GL diets, low GI/GL dietary patterns reduced HbA1c (mean difference, −0.31%; heterogeneity, I2 = 75%). Reductions were also seen in fasting glucose, low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol (HDL-C), apolipoprotein B, triglycerides, body weight, body mass index, and C-reactive protein; no reductions were seen in blood insulin, HDL-C, waist circumference, or blood pressure. For the difference in GL and HbA1c and for absolute dietary GI and systolic blood pressure, positive dose-response gradients were observed. For the reduction in HbA1c, the certainty of evidence was high; moderate-certainty evidence was seen for most secondary outcomes.
“Our synthesis supports existing recommendations for the use of low GI/GL dietary patterns in the management of diabetes,” the authors write.
Several authors disclosed financial ties to nutrition and other industries.