Table. 1.
Table. 1.
Characteristics of included studies
| Reference | Design | No. of participants (sex) | Mean age (year) | Type and amount of green tea | Duration | Notes about participants | Main outcome |
|---|---|---|---|---|---|---|---|
| Bazyar et al., 2020 | Double-blind/parallel | Placebo=22 (10 male) Green tea=22 (11 male) |
Placebo=52.61±7.22 Green tea=51.75±6.79 |
300 mg/d epigallocatechin-3-gallate | 2 months | T2DM with duration of more than 2 years, were recruited from outpatient, without insulin injection | IL-6 |
| Hadi et al., 2020 | Double-blind/parallel | Placebo=22 (10 male) Green tea=22 (9 male) |
Placebo=54.84±5.96 Green tea=51.47±8.42 |
300 mg/d epigallocatechin-3-gallate | 8 weeks | T2DM without insulin therapy or diabetic treatment history that lasted for three months | CRP |
| Mombaini et al., 2017 | Double-blind/parallel | Placebo=23 (female) Green tea=22 (female) |
Placebo=24.17±6.83 Green tea=23.22±5.24 |
500 mg/d green tea leaf powder | 45 days | Polycystic ovary syndrome screened from a gynecology clinic, without combined diseases | CRP, IL-6, TNF-α |
| Hussain et al., 2017 | Double-blind/parallel | Placebo=40 (26 male) Green tea=40 (28 male) |
Placebo=28±15 Green tea=25±18 |
500 mg/d green tea extract | 12 weeks | NAFLD patients were recruited from outpatient, with elevated aminotransferases (mild to moderate) and ultrasound with fatty liver grading 1, 2, 3 | CRP |
| Gutiérrez-Salmeán et al., 2016 | Double-blind/parallel | Placebo=10 (NR) Green tea=20 (NR) |
18~55 | 100 mg/d epicatechin | 4 weeks | Hypertriglyceridemia (200~499 mg/dL) without medication other than statins at a stable dose of ≥6 weeks | CRP |
| Borges et al., 2016 | Double-blind/parallel | Placebo=21 (16 male) Green tea=21 (11 male) |
Placebo=59 (49~63) Green tea=63 (60~65) |
800 mg/d epigallocatechin gallate | 12 weeks | Diabetic type 1 or 2 with nephropathy during routine visits in hospital, treatment with maximum doses of ACE inhibitors and/or ARBs for at least 8 weeks prior to the screening | CRP, TNF-α |
| Nogueira et al., 2017 | Double-blind/crossover | 20 (female) | 41.1±8.4 | 500 mg/d green tea extract | 4 weeks | Obese prehypertensive women, recruited at the Department of Plastic Surgery among the candidates for lipoplasty, without any medication known to interfere with body weight, blood pressure, and metabolic profile | CRP, IL-6, TNF-α |
| Dower et al., 2015 | Double-blind/crossover | 37 (25 male) | 66.4±7.9 | 100 mg/d epicatechin | 4 weeks | (Pre)hypertensive without chronic diseases or users of medication | CRP, IL-6, TNF-α |
| Liu et al., 2014 | Double-blind/parallel | Placebo=38 (18 male) Green tea=39 (14 male) |
Placebo=53.5±7.0 Green tea=55.0±6.6 |
500 mg/d green tea extract | 16 weeks | T2DM (glycemic hemoglobin higher than 6.5% within 3 months) and lipid abnormalities (fasting triglyceride≥150 mg/dL or fasting low-density lipoprotein (LDL) cholesterol≥100 mg/dL) | CRP |
| Mielgo-Ayuso et al., 2014 | Double-blind/parallel | Placebo=39 (female) Green tea=39 (female) |
19~49 | 300 mg/d epigallocatechin-3-gallate | 12 weeks | Obese women with total cholesterol levels≤7 758 mmol/L, TAG levels≤3 387 mmol/L and blood pressure levels≤140/90 mmHg. Women free of medication for hypertension, hyperlipidemia, hyperuricemia or other illness | CRP |
| Bogdanski et al., 2012 | Double-blind/parallel | Placebo=28 (15 male) Green tea=28 (13 male) |
Placebo=51.5±7.4 Green tea=49.2±8.8 |
379 mg/d green tea extract | 3 months | Obese and hypertensive screened at our outpatient clinic with BMI≥30 kg/m2 and blood pressure levels ≤160/100 mmHg. Stable treatment for at least 6 months | CRP, TNF-α |
| Basu et al., 2011 | Single-blind/parallel | Placebo=12 (2 male) Green tea=13 (3 male) |
Placebo=44.6±3.2 Green tea=42.8±2.6 |
110 mg/d green tea extract | 8 weeks | Obese subjects with metabolic syndrome with stable medications (except hypoglycemic and hypolipidemic agents) | CRP, IL-6 |
| Basu et al., 2011 | Single-blind/parallel | Placebo=12 (2 male) Green tea=10 (3 male) |
Placebo=44.6±3.2 Green tea=39.5±3.0 |
500 mg/d green tea extract | 8 weeks | Obese subjects with metabolic syndrome with stable medications (except hypoglycemic and hypolipidemic agents) | CRP, IL-6 |
| Mohammadi et al., 2010 | Double-blind/parallel | 58 (8 male) | 36.5±14.55 | 4.5 g/d of green tea extract | 8 weeks | T2DM with duration of more than 2 years, were recruited from outpatient. Taking oral medications to control blood sugar and not having a history suffering from other diseases | CRP |
| Fukino et al., 2008 | Without blinding/crossover | 60 (49 male) | Placebo=53.97±8.6 Green tea=53.47±7.7 |
500 mg/d green tea extract | 2 months | Glucose abnormalities (fasting blood glucose level of ≥6.1 mmol/L or a nonfasting blood glucose level of ≥7.8 mmol/L) | CRP |
| Fukino et al., 2005 | Parallel | Placebo=33 (26 male) Green tea=33 (27 male) |
Placebo=53.5±7.5 Green tea=53.5±8.5 |
500 mg/d green tea extract | 2 months | Borderline diabetes or diabetes (fasting blood glucose level of ≥110 mg/dL or a nonfasting blood glucose level of ≥140 mg/dL) | CRP |
Values are presented as mean±SD.
T2DM, type 2 diabetes mellitus; NAFLD, non-alcoholic fatty liver disease; ACE, angiotensin converting enzyme; ARBs, angiotensin receptor blockers; TAG, triacylglycerols; BMI, body mas index; IL-6, interleukin-6; CRP, C-reactive protein; TNF-α, tumor necrosis factor-α; NR, not reported.
Prev Nutr Food Sci 2024;29:106~117 https://doi.org/10.3746/pnf.2024.29.2.106
© Prev. Nutr. Food Sci.