Fiber-enriched formula linked to improved health-related quality of life, HbA1c in type 2 diabetes

A prebiotic fiber-enriched nutritional formula was associated with improved measures of health-related quality of life and metabolic control in type 2 diabetes, an industry-funded trial found.

Researchers conducted a double-blind, placebo-controlled trial that randomized participants 2:1:1 to receive a fiber-enriched nutritional shake made by Supergut, a placebo shake without fiber, or dietary advice only in an unblinded comparator arm. They enrolled participants across the U.S. using virtual communication and a decentralized trial design and conducted the trial from Oct. 20, 2021, to May 16, 2022. Eligible participants had self-reported type 2 diabetes for at least 90 days, had self-reported HbA1c levels of 7.5% to 10.5%, had self-reported body mass index of 27 to 50 kg/m², and were treated with diet and exercise alone or with a stable dose of antidiabetic medication. Nutritional formulas were escalated over the course of three weeks to a maximally tolerated dose of two shake packets, with at least one replacing a meal, and were continued for 12 weeks. All participants received general dietary recommendations, including the CDC Living With Diabetes online resource, and continued all baseline diabetes therapies throughout the study. Participants also had their gut microbiomes collected and analyzed during the trial. The primary end point was change from baseline to week 12 in core Type 2 Diabetes Distress Assessment System score, with a positive mean change of 0.25 from baseline considered to be clinically meaningful. Secondary end points included changes in HbA1c level, fasting plasma glucose level, body weight and microbiome analysis. The study was supported by funds provided by Supergut, and several study authors were Supergut employees. Results were published Jan. 3 by Diabetes, Obesity and Metabolism.

The study randomized 192 participants (mean age, 54.3 years; 62.0% female), 95 to the active group, 48 to the placebo group, and 49 to the diet group. Due to a higher-than-anticipated dropout rate (active, 19%; placebo, 28%; diet, 27%), additional subjects beyond sample-size calculations were enrolled. From baseline to week 12, core Type 2 Diabetes Distress Assessment System score decreased by a mean of 3.1 to 2.8 in the active arm, increased from 3.0 to 3.1 in the placebo arm, and remained unchanged from 3.1 in the diet arm (three-way P=0.03). At 12 weeks, the mean change in HbA1c level was −0.36%, 0.30%, and −0.17% in the active, placebo, and diet arms, respectively. The mean difference between the change in HbA1c level in the active and placebo arms was −0.66% (P=0.01). Fasting plasma glucose level did not change significantly from baseline to week 12 in all three arms, whereas change in body weight from baseline was −1.36 kg for the active arm, −0.64 kg for the placebo arm, and −0.54 kg for the diet arm, with the active arm showing significantly greater weight reduction compared with the diet arm (P=0.03). Microbiomes were not significantly changed by the interventions, but the authors reported an increase in the abundance of favorable bacteria in the active versus placebo groups.

The decentralized trial design likely contributed to the higher-than-anticipated dropout rate, among other limitations, the authors noted. They added that the study was of relatively short duration and was conducted during the U.S. holiday season, potentially adversely affecting metabolic outcomes. “Future studies powered for metabolic outcomes such as HbA1c will be necessary to confirm these findings,” they wrote.