Cinnamon can be used as an additional treatment to control glycemic indices and act as an antidiabetic agent in patients with type 2 diabetes (T2D) or polycystic ovary syndrome (PCOS), according to a study published in Diabetology and Metabolic Syndrome.
Researchers performed an umbrella meta-analysis by selecting relevant studies from PubMed, Scopus, EMBASE, Web of Science, and Google Scholar to determine the effects of cinnamon on glycemic control in patients with T2D or PCOS. Randomized clinical trials evaluating the effect of cinnamon on glycemic indices, including fasting plasma glucose (FPG), homeostatic model assessment for insulin resistance (HOMA-IR), insulin, and hemoglobin A1C (HbA1c), were included in the meta-analysis.
A total of 11 meta-analyses of randomized clinical trials between 2008 and 2021 were included in the current study. The titles and abstracts were reviewed before being included as well as the full text of the studies to determine relevance. Only studies in English were included. Case reports, observational, in vitro, in vivo, and quasiexperimental studies were excluded. Cinnamon supplements were dosed at a range of 0.12 g/day and 14.4 g/day with median dose of 3.76 g/day.
According to the weighted mean difference analysis, cinnamon supplementation lowered serum FPG levels (SD, -0.86) by 10.93 mg/dL in 6 studies (95% CI, -16.22 to -5.65; P =.01). Results of the standardized mean difference analysis also demonstrated lower FPG levels (95% CI, -1.19 to -0.52; P =.01) in 5 studies, with the most significant difference in patients with T2D. The researchers also noted lower HbA1c levels (0.10%; 95% CI, -0.17 to -0.03), insulin by 2.01 IU/mL (95% CI, -3.96 to -0.07; P =.04). The HOMA-IR levels of patients were also lower with cinnamon supplementation (0.61; 95% CI, -0.91 to -0.31; P =.01).
Study limitations include the use of different types of cinnamon per study, supplementation dosage and study duration were not available for all studies, and differences in the baseline values of the different T2D biomarkers across the different studies.
“Cinnamon can be used as an anti-diabetic agent and an add-on treatment to control some glycemic indices among T2D patients and women with PCOS,” the researchers concluded.
Zarezadeh M, Musazadeh V, Foroumandi E, et al. The effect of cinnamon supplementation on glycemic control in patients with type 2 diabetes or with polycystic ovary syndrome: an umbrella meta-analysis on interventional meta-analyses. Diabetol Metab Syndr. Published online June 15, 2023. doi:10.1186/s13098-023-01057-2