Propolis Supplementation for Glycemic Control and Inflammation in Type 2 Diabetes Mellitus: A Review

Abstract

Propolis contains polyphenols and other bioactive compounds with antioxidant and immunomodulatory activity, but its clinical value in type 2 diabetes mellitus (T2DM) remains uncertain because products, doses, outcomes, and reporting vary substantially. The aim of this review was to critically synthesize evidence on propolis supplementation for glycemic control and inflammation in adults with T2DM, with particular attention to direct comparison with standard medication. This structured narrative review reorganized 16 records from google scholar and semantic scholar database. Most placebo-controlled trials reported improvements in one or more glycemic indices, although null findings also occurred. Effects on inflammatory markers were less consistent. A single 36-participant, 12-week trial compared propolis (600 mg/day) with metformin (1,700 mg/day); both groups improved from baseline, but the study was not designed to demonstrate equivalence or non-inferiority. Recent meta-analyses suggest small average reductions in fasting glucose and HbA1c, with substantial clinical and methodological heterogeneity. Propolis supports a clinical research hypothesis as an adjunctive nutraceutical, not an established alternative to diabetes medication. Larger preregistered trials using chemically standardized products, clinically meaningful endpoints, adequate safety monitoring, and active-comparator designs are needed.