49-LB: A Low Biologically Available Glucose Diet Reduces Hemoglobin A1c in Type 2 Diabetes Mellitus—A Randomized Controlled Trial

Introduction: The Low Biologically Available Glucose (LoBAG) diet was designed to improve glycemic control of type 2 diabetes mellitus (T2D). This study tested the effectiveness of the diet in free-living participants with T2D.

Methods: A 12-week randomized controlled trial in participants with T2D compared the LoBAG₃₀ diet (30% low starch carbohydrate, 30% protein, 40% fat) to a control diet (55% carbohydrate, 15% protein, 30% fat). Participants were taking metformin at a stable dose or no glucose-lowering medication. Diets were prescribed to be weight neutral and participants were asked to keep physical activity level constant. Diet instruction and dietitian support were provided to both study groups; food was not provided. The primary outcome was hemoglobin A1c (HbA1c) at the end of the intervention, compared between groups.

Results: Forty-eight participants were enrolled (30 female/18 male; 77% white, 15% Black/African American, 2% Asian, 2% American Indian, 4% not reported; 15% Hispanic/Latino). The majority (88%) took metformin. Baseline characteristics were mean (SD) age 57.4 (10.4) years, HbA1c 7.7 (0.6) %, weight 101.5 (19.7) kg, and BMI 35.4 (5.9) kg/m² with no significant differences between groups. Thirty-eight participants completed the entire intervention; 4/10 non-completers were withdrawn due to the COVID-19 pandemic. HbA1c decreased in both groups over 12 weeks: mean (SD) -1.0 (0.8) % for the LoBAG diet (p<0.01) and -0.6 (0.7) % for control (p<0.01). The final HbA1c was 6.6 (0.6) % in the LoBAG diet group versus 7.2 (0.8) % for control (p=0.01 for comparison between groups). Both groups lost weight: -6.0 (6.9) kg with the LoBAG diet versus -4.3 (3.5) kg for control (p=0.34 for comparison between groups).

Conclusion: Participants with T2D consuming the LoBAG diet had greater reduction in HbA1c over 12 weeks than those consuming a control diet. The LoBAG diet is an effective option for dietary management of blood glucose in patients with T2D.