Nutritional Recommendations for Type 2 Diabetes: An International Review of 15 Guidelines

Recommendations from clinical practice guidelines (CPGs) for individuals with type 2 diabetes mellitus (T2DM) may be inconsistent, and little is known about their quality. Our aim in this study was to systematically review the consistency of globally available CPGs containing nutritional recommendations for T2DM and to assess the quality of their methodology and reporting.

PubMed, China Biology Medicine and 4 main guideline websites were searched. Four researchers independently assessed quality of the methodology and reporting using the Appraisal of Guidelines for Research and Evaluation, second edition (AGREE II) instrument and the Reporting Items for Practice Guidelines in HealThcare (RIGHT) checklist.

Fifteen CPGs include 65 nutritional recommendations with 6 sections: 1) body weight and energy balance; 2) dietary eating patterns; 3) macronutrients; 4) micronutrients and supplements; 5) alcohol; and 6) specific, functional foods. Current nutritional recommendations for individuals with T2DM on specific elements and amounts are not completely consistent in different CPGs and fail to assign the specific supporting evidence and strength of recommendations. To use nutritional recommendations to guide and manage individuals with T2DM, it is important to address the current challenges by establishing a solid evidence base and indicating the strength of recommendations. Overall, 8 CPGs classified as recommended for clinical practice used AGREE II. Fifteen CPGs adhere to <60% of RIGHT checklist items.

High-quality evidence is needed to potentially close knowledge gaps and strengthen the recommendation. The AGREE II instrument, along with the RIGHT checklist, should be endorsed and used by CPG developers to ensure higher quality and adequate use of their products.