TABLE 3.

The characteristics of the included studies regarding to the effect of anthocyanins on Gamma‐glutamyl transferase (GGT) levels

Study	Study design	Study population	Type of intervention	Anthocyanins dose (mg/day)	Trial duration	GGT levels (U/L)
						Baseline	End of trial
1. Oki et al. (2016)	Randomized double‐blind, placebo‐controlled clinical trial (parallel)	Healthy Caucasians with borderline hepatitis. Total n = 40. But n = 37 (18 in PSP group and 19 in placebo group) completed the study	Anthocyanin‐rich purple‐fleshed sweet potato (PSP) beverage or placebo	531	8 weeks	PSP group: 74.6 ± 35.1 Placebo group: 57.1 ± 16.7	PSP group: Not reported Placebo group: Not reported
2. Suda et al. (2008)	Randomized double‐blind placebo‐controlled clinical trial (parallel)	Healthy men with borderline hepatitis. Total n = 48. But n = 38 (n = 20 in PSP group and n = 18 in placebo group) completed the study	Purple sweet potato (PSP) beverage or placebo	400.6	12 weeks	PSP group: **103.6 (17.3) Placebo group: **91.6 (11.1)	PSP group: Not reported Placebo group: Not reported
3. Curtis et al. (2009)	Randomized double‐blind placebo‐controlled clinical trial (parallel)	Healthy postmenopausal women. Total n = 56. N = 26 completed the study	Elderberry extract or placebo	500	12 weeks	Elderberry group: 21.0 ± 14.2 Placebo group: 22.0 ± 16.3	Elderberry group: 18.3 ± 9.5 Placebo group: 19.0 ± 11.5
4. Chang et al. (2014)	Randomized double‐blind placebo‐controlled clinical trial (parallel)	Subjects with a BMI higher than 27 and NAFLD. Total n = 40. But n = 36 (n = 19 in HSE group and n = 17 in placebo group) completed the study	Hibiscus sabdariffa extracts (HSE) or placebo	67.5	12 weeks	HSE group: 49.26 ± 45.39 Placebo group: 40.88 ± 32.57	HSE group: 50.05 ± 40 Placebo group: 35.65 ± 26.08

All values expressed as mean ± standard deviation (SD) except **for study number 2: Values presented as mean (95% CI).