Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2025 Jan;26(1):e13837.
doi: 10.1111/obr.13837. Epub 2024 Sep 19.

Higher fiber higher carbohydrate diets better than lower carbohydrate lower fiber diets for diabetes management: Rapid review with meta-analyses

Andrew N Reynolds  1   2 , Jessica Lang  2 , Amanda Brand  3 , Jim Mann  1   2
Affiliations
Meta-Analysis

Higher fiber higher carbohydrate diets better than lower carbohydrate lower fiber diets for diabetes management: Rapid review with meta-analyses

Andrew N Reynolds et al. Obes Rev. 2025 Jan.

Abstract

Background: Some dietary recommendations continue to recommend carbohydrate restriction as a cornerstone of dietary advice for people with diabetes.

Purpose: We compared the cardiometabolic effects of diets higher in both fiber and carbohydrate with lower carbohydrate lower fiber diets in type 1 or type 2 diabetes.

Data sources: MEDLINE, Embase, and the Cochrane Database of Systematic Reviews up to June 24, 2024, with additional hand searching.

Study selection: Randomized controlled trials in which both dietary fiber and carbohydrate amount had been modified were identified from source evidence syntheses on carbohydrate amount in people with diabetes.

Data extraction: Two reviewers independently.

Data synthesis: Ten eligible trials including 499 participants with diabetes (98% with T2) were identified from the potentially eligible 828 trials included in existing evidence syntheses. Pooled findings indicate that higher fiber higher carbohydrate diets reduced HbA1c (mean difference [MD] -0.50% [95% confidence interval -0.99 to -0.02]), fasting insulin (MD -0.99 μIU/mL [-1.83 to -0.15]), total cholesterol (MD -0.16 mmol/L [-0.27 to -0.05]) and low-density lipoprotein cholesterol (MD -0.16 mmol/L (-0.31 to -0.01) when compared with lower carbohydrate lower fiber diets. Trials with larger differences in fiber and carbohydrate intakes between interventions reported greater reductions. Certainty of evidence for these outcomes was moderate or high, with most outcomes downgraded due to heterogeneity unexplained by any single variable.

Limitations: Our predefined scope excluded trials with co-interventions such as energy restriction, which may have provided addition information.

Conclusions: Findings indicate the greater importance of promoting dietary fiber intakes, and the relative unimportance of carbohydrate amount in recommendations for people with diabetes.

Keywords: carbohydrate metabolism; dietary guidelines; meta‐analysis; public health; type 2 diabetes.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

FIGURE 1
FIGURE 1
Flowchart illustrating the identification of eligible evidence syntheses and trials.
FIGURE 2
FIGURE 2
Higher‐carbohydrate higher‐fiber diets compared with lower‐carbohydrate lower‐fiber diets in diabetes management. *One trial that provided different instruction on sodium intake between intervention arms was removed before analysis of these outcomes.
FIGURE 3
FIGURE 3
Dose response testing for carbohydrate and fiber difference between intervention arms.
See this image and copyright information in PMC

References

    1. Mann J, Truswell S, Hodson L. Essentials of human nutrition 6e. UK, Oxford University Press; 2023. doi:10.1093/hesc/9780198866671.001.0001 - DOI
    1. The Diabetes Nutrition Study Group of the European Association for the Study of Diabetes (DNSG) . Evidence‐based European recommendations for the dietary management of diabetes. Diabetologia. 2023;66(6):965‐985. doi:10.1007/s00125-023-05894-8 - DOI - PubMed
    1. World Health Organization . Carbohydrate intake for adults and children: WHO guideline. In Carbohydrate intake for adults and children: WHO guideline, 2023. - PubMed
    1. Reynolds A, Mann J, Cummings J, Winter N, Mete E, Te Morenga L. Carbohydrate quality and human health: a series of systematic reviews and meta‐analyses. The Lancet. 2019;393(10170):434‐445. doi:10.1016/S0140-6736(18)31809-9 - DOI - PubMed
    1. Blomhoff R, Andersen R, Arnesen EK, et al. Nordic nutrition recommendations 2023: integrating environmental aspects. Nordic Council of Ministers. 2023. doi:10.6027/nord2023-003 - DOI

MeSH terms