High dietary GI, GL intakes nix weight management in overweight, obese adults

Increased consumption of foods with high glycaemic index (GI) and load (GL) leads to weight regain and glycaemic status worsening in overweight or obese individuals undergoing weight loss maintenance (WLM), a study has found.

Researchers conducted a secondary analysis of the PREVIEW* trial, which included 1,279 participants (age 25–70 years, body mass index ≥25 kg/m²) with prediabetes at baseline. The trial tested the effects of four diet and physical activity interventions. 

Multiadjusted linear mixed models showed that participants in the high vs low tertiles of GI and GL had a greater weight regain and increases in HbA1c. In the available-case and complete-case analyses, each 10-unit increment in GI correlated with a weight increase of 0.46 kg per year (95 percent confidence interval [CI] 0.23–0.68; p<0.001). Meanwhile, each 20-unit increment in GL was associated with an increase of 0.49 kg per year (95 percent CI 0.24–0.75; p<0.001).

Weight change did not modify the associations of GI and GL with HbA1c.

Higher fibre intake, on the other hand, contributed to reductions in waist circumference, but the associations for weight regain and HbA1c did not remain robust in different analyses.

More studies are needed to establish the role of fibre.

*PREVention of diabetes through lifestyle Intervention and population studies in Europe and around the World