A small Chinese study indicates that a structured high-fibre diet could not only improve blood sugar control and reduce body weight more effectively than metformin, but also positively alter gut bacteria associated with metabolic health, offering new insights into dietary management of type 2 diabetes.
A small Chinese trial suggests that a carefully structured high-fibre diet may do more than help people with newly diagnosed type 2 diabetes lose weight. According to a report in Frontiers in Microbiology highlighted by News-Medical, the intervention improved blood sugar control and body mass more than metformin alone over 84 days, while also shifting the gut microbiome in ways that may matter for metabolism.
Researchers at Henan Provincial People’s Hospital in China enrolled 48 adults with newly diagnosed type 2 diabetes and obesity, of whom 46 completed the study. After a two-week run-in period, participants were assigned either to a high-fibre dietary programme without medication or to metformin monotherapy. The dietary approach used fibre formulas containing soluble and insoluble components such as inulin and resistant dextrin, with the main endpoints measured at day 84. The trial also tracked continuous glucose monitoring, meal tolerance responses, body composition and stool samples to assess changes in gut bacteria and microbial by-products.
By the end of the study, the fibre group had lower adjusted glycated haemoglobin, or HbA1c, and a lower body mass index than the metformin group. It also showed less glycaemic variability, lower whole-body fat mass and reduced triglycerides. The article reports that people in the dietary arm ate less energy overall and consumed smaller amounts of several macronutrients, which may have contributed to the weight-related benefits. These findings fit with a broader body of research linking dietary fibre to improved metabolic control in type 2 diabetes, including earlier work in Diabetes suggesting that increasing fibre intake can help patients already taking metformin.
The microbiome results were equally notable. Shotgun metagenomic analysis showed that the high-fibre regimen quickly altered the structure of the gut community, enriching bacteria such as Bifidobacterium and Lactobacillus while reducing Bilophila wadsworthia, a microbe associated with chronic inflammation. The study also found changes in genes involved in acetate production and lower abundance of genes linked to hydrogen sulphide production in the fibre group. That matters because review papers in Biomedicines and related journals have described how gut bacteria ferment fibre into short-chain fatty acids, which can stimulate GLP-1 release, improve insulin sensitivity and increase satiety. Other reviews, including one in Current Diabetes Reports, have also argued that dysbiosis may contribute to obesity and type 2 diabetes by disturbing metabolic regulation.
Even so, the authors and outside reviewers would treat the results as promising rather than definitive. The trial was single-centre, short in duration and small, with only 12 people in the metformin arm, which limits how confidently the findings can be generalised. GLP-1 was not directly measured, so the proposed pathway from fibre to short-chain fatty acids to hormonal and metabolic change remains inferential. The study nevertheless adds to a growing case that gut-targeted dietary therapy could become a practical part of managing type 2 diabetes, especially in people whose excess weight and blood sugar problems are closely linked.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
