TABLE 1.

Characteristics of included studies.

Author	Publication year	Population/Country	Sample size (control/intervention)		Daily dose	Main characteristics of medications	Duration	Age (y) (control/intervention)
			Control	Intervention				Control	Intervention
Vanschoonbeek et al., 2006	2006	Netherlands	13	12	1.5 g/d	Oral antidiabetic	6 weeks	64 ± 2	62 ± 2
Mang et al., 2006	2006	Germany	32	33	3 g/d	Oral antidiabetic	16 weeks	63·7 ± 7·17	62·8 ± 8·37
Blevins et al., 2007	2007	United States	28	29	1 g/d	Oral antidiabetic and hypolipidemia	12 weeks
Crawford, 2009	2009	United States	54	55	1 g/d	Oral antidiabetic and insulin	12 weeks	59.9 ± 9.2	60.5 ± 10.7
Akilen et al., 2010	2010	United Kingdom	28	30	2 g/d	Oral antidiabetic	12 weeks	54.43 ± 12.53	54.90 ± 10.14
Wainstein et al., 2011	2011	Israel	30	29	1.2 g/d	Metformin and/or sulfonylurea	12 weeks	64.4 ± 15.4	61.7 ± 6.3
Vafa et al., 2012	2012	Iran	18	19	3 g/d	Metformin and gliclazide	8 weeks	55.67 ± 7.98	54.11 ± 10.37
Lu et al., 2012	2012	China	20	23	4.8 g/d	Gliclazide	12 weeks	60 ± 5.9	62.4 ± 7.9
Lu et al., 2012	2012	China	20	23	14.4 g/d	Gliclazide	12 weeks	60 ± 5.9	58.9 ± 6.4
Hasanzade et al., 2013	2013	Iran	35	35	1 g/d	Oral antidiabetic	8 weeks	54.7 ± 8.1	53.7 ± 9.7
Azimi et al., 2014	2014	Iran	39	40	3 g/d	Metformin and glibenclamide	8 weeks	53.64 ± 1.3	54.15 ± 1.0
Mirfeizi et al., 2016	2016	Iran	30	30	1 g/d	Sulfonylurea, biguanides, and/or thiazolidines	12 weeks	54 ± 12	55 ± 10
Talaei et al., 2017	2017	Iran	19	20	3 g/d	Metformin and insulin	8 weeks	56.26 ± 9.46	58.90 ± 7.93
Zare et al., 2019	2019	Iran	69	69	1 g/d	Oral hypoglycemic agents	12 weeks	53.2 ± 8.5	52.1 ± 9.7
Mirmiranpour et al., 2020	2020	Iran	27	28	0.5 g/d	Oral antidiabetic	12 weeks	58.2 ± 11	58.8 ± 12.8
Lira Neto et al., 2021	2021	United States	69	71	3 g/d	Oral antidiabetic	12 weeks	60.8 ± 10.8	61.7 ± 11.7