Table 1. Characteristics of the randomized controlled trial studies included.

Study	Country	Year	Participants		Sample size (control/intervention)	Intervention	Control	Duration	Outcomes
			Health status	Mean age (SD)
Han et al. [17]	Brazil	2002	Healthy, menopause	48.5 (1.2)	40/40	Isoflavone 100 mg per day	Placebo	4 mon	Kupperman Index, estradiol, FSH, LH
Steinberg et al. [18]	USA	2011	Healthy, menopause	54.8 (3.9)	134/135 (80 mg), 136 (120 mg)	Isoflavone 80 mg or 120 mg per day	Placebo	1 yr	Estradiol, FSH, LH
Maskarinec et al. [19]	USA	2004	Healthy, premenopause	42.8 (2.9)	110/108	Isoflavone 100 mg per day	Placebo	2 yrs	Estradiol
Sapbamrer et al. [21]	Thailand	2013	Healthy, menopause	56.65 (2.56)	29/31	Fermented soybean (isoflavone 60 mg) per day	Placebo	6 mon	Estradiol
Lee et al. [20]	Korea	2017	Healthy, menopause	53.6 (3.4)	43/41	Isoflavone 70 mg per day	Placebo	12 wk	Hot flashes, Kupperman Index
Jou et al. [22]	Taiwan	2008	Healthy menopausal women	53.9 (3.4)	27/31	3 g of soy germ extract twice per day (135 mg of isoflavones)	Placebo	6 mon	Hot flashes
Radhakrishnan et al. [23]	India	2009	Healthy menopausal women	47.1 (6.36)	41/44	25 g isoflavone rich soy protein (75 mg isoflavones) per day	Placebo	6 mon	Hot flashes, Kupperman Index, estradiol, FSH
St Germain et al. [24]	USA	2001	Healthy perimenopausal women	50 (median)	21/24	Isoflavone-rich soy protein (80.4 mg isoflavones aglycones) per day	Whey protein control	24 wk	Hot flashes
Cheng et al. [27]	Sweden	2007	Healthy menopausal women	57.6 (4.6)	25/26	Fruit drink containing isoflavones (60 mg isoflavones) per day	Placebo	12 wk	Hot flashes, estradiol, FSH
Liu et al. [28]	Hong Kong	2014	Healthy menopausal women	57.9 (5)	90/90	40 g of whole soy flour (49.3 mg isoflavone) or Daidzein (63 mg isoflavone) per day	Placebo	6 mon	Hot flashes
Llaneza et al. [26]	Spain	2012	Healthy menopausal women	56.7 (3.5)	32/33	Soy isoflavone extract (80 mg isoflavones) per day	Control	6–24 mon	Kupperman Index, estradiol

FSH, follicle stimulating hormone; LH, luteinizing hormone.