Table 1 Characteristics of included studies
Citation (First author et al., year) | No. of Studies in Meta-analysis | Location Duration of intervention | No. of Participants in Meta-analysis | Intervention/daily dose | Quality Assessment Scale and Rating | Measured outcomes and Results |
|---|---|---|---|---|---|---|
Kutbi et al. 2021 | 23 | Saudi Arabia 11 | 1516 with metabolic diseases | Cinnamon/2.2 g/day | Yes (Cochrane) 23/23 were low | FPG (↓), HOMA (↓), HbA1C(↓), Insulin (↓) |
Heshmati et al.2021 | 5 | Iran 8-52wk | 289 with PCOS | Cinnamon /0.5–1.5 g/day | Yes (Cochrane) 3/5 were high | FPG(↓), HOMA(↓), insulin(↓) |
Heydarpour et al.2020 | 5 | Iran 6-24wk | 448 with PCOS | Cinnamon/ 0.336-1.5 g/day | Yes (Cochrane) 3/5 were high | FPG(↓), HOMA (↓), insulin (↓) |
Namazi et al.2019 | 18 | Iran 6-17wk | 1100 with T2DM | Powder and extract of cinnamon/ 1–6 g/day of powder and 0.12 − 0.5 g/day of extract | Yes (Cochrane) 13/18 were low | FPG (↓), HbA1C (↓) |
Deyno et al.2019 | 16 | Uganda 4-16wk | 1098 with T2DM | Cassia, aromaticum, zeylanicum and verum/1-14.4 g/day | Yes (Cochrane) 8/16 were high | FPG (↓), HOMA (↓), HbA1C(Ns), Insulin (↓) |
Ainehchi et al.2019 | 16 | Iran NR | 668 with PCOS | Cinnamon /without restrictions regarding dose | Yes (Cochrane) 7/16 were high | FPG (↓) |
Allen et al.2013 | 10 | USA 4-18wk | 543 with T2DM | Aqueous cinnamon extract or raw cinnamon powder/0.12-6 g/day | Yes (Cochrane) 5/10 were high | FPG (↓), HbA1C (Ns) |
Akilen et al.2012 | 6 | UK 6-16wk | 375 with T2DM | Cinnamomum cassia/1–6 g/day | Yes (Cochrane) 2/6 were high | FPG (↑), HbA1C (↑) |
Leach et al.2012 | 6 | Australia 4-16wk | 577 with T2DM | Cassia, Chinese cinnamon and burmanii/2Â g/day | Yes (Cochrane) 3/10 were high | FPG(Ns),HbA1C (Ns),insulin (Ns) |
Davis et al.2011 | 8 | USA 4–16 wk | 369 with T2DM | 1–6 g cinnamon and 250 mg-3 g cinnamon extract | Yes (Cochrane) 3/8 were high | FPG(↓) |
Baker et al.2008 | 4 | USA 12 | 207 with T2DM | Cinnamon/3.5Â g/day | NR | FPG (Ns), HbA1C(Ns) |