Published in 2020, this review highlights the evidence relating to a mechanism of action as well as eight clinical studies that outline the use of cinnamon for blood sugar regulation. With authors concluding that as a “complementary therapy, it should not be viewed as an alternative to established glucose lowering drugs. While the exact dose is not clear, one may recommend use of up to one teaspoonful of cinnamon powder as an adjunct to therapy.”
Sharma S, Mandal A, Kant R, Jachak S, Jagzape M. Is Cinnamon Efficacious for Glycaemic Control in Type-2 Diabetes Mellitus? J Pak Med Assoc. 2020 Nov;70(11):2065-2069. PMID: 33341863.