Table 2.
Characteristics of included studies
| Author, Year (Location) | Study design | Population | Gender | Number (Case/control) | Intervention Mean (range) age (years) | Intervention Mean BMI (kg/m2) | Duration (Weeks) | Intervention Intervention group Control group |
Outcome |
|---|---|---|---|---|---|---|---|---|---|
| Van het Hof et al., 1997 (Netherlands) |
RCT, Parallel | Healthy | M/F | 14/16 | 37 | 23.72 | 4 | Green Tea (3 g/day) Placebo |
TAC MDA GPx SOD |
| De Maat et al., 2000 (Netherlands) (a) |
RCT, Parallel | Smoking healthy individuals | M/F | 15/15 | 32 | 22 | 4 | Green Tea (3 g/day) Placebo |
CRP TNFα IL-1β IL-6 |
| De Maat et al., 2000 (Netherlands) (b) |
RCT, Parallel | Smoking healthy individuals | M/F | 13/15 | 33 | 22 | 4 | Green Tea (9 g/day) Placebo |
CRP TNFα IL-1β IL-6 |
| Erba et al., 2007 (Italy) |
RCT, Parallel | Healthy | M/F | 12-Dec | 19.1 | NR | 6 | Green Tea Catechins (250 mg/day) Placebo |
MDA GPx |
| Fukino et al., 2008 (Japan) (a) |
RCT, Crossover | T2DM and prediabetes | M/F | 29/31 | 53.9 | 25.4 | 8 | Green Tea Catechins (456 mg/day) Placebo |
CRP |
| Fukino et al., 2008 (Japan) (b) |
RCT, Crossover | T2DM and prediabetes | M/F | 31/29 | 53.5 | 26 | 8 | Green Tea Catechins (456 mg/day) Placebo |
CRP |
| Mohammadi et al., 2010 (Iran) |
RCT, Parallel | T2DM | M/F | 29/29 | 55.14 | 28.64 | 8 | Green Tea Extract (1500 mg/day) Placebo |
CRP |
| Li et al., 2010 (USA) |
RCT, Parallel | Older Adults | M/F | 20/20 | 59 | 24.2 | 16 | Green Tea Extract (200 mg/day) + Lutein Placebo + Lutein |
MDA |
| Basu et al., 2011 (USA) (a) |
RCT, Parallel | MetS | M/F | 13-Dec | 42.8 | 36.1 | 8 | EGCG (440 mg/day – Brewed Green Tea) Placebo |
CRP IL-1β IL-6 |
| Basu et al., 2011 (USA) (b) |
RCT, Parallel | MetS | M/F | 10-Dec | 39.5 | 36.1 | 8 | EGCG (500 mg/day - Capsule) Placebo |
CRP IL-1β IL-6 |
| Sone et al., 2011 (Japan) |
RCT, Crossover | Healthy | M/F | 25/26 | 43.2 | 24.6 | 9 | Green Tea Catechins (400 mg/day) Placebo |
CRP |
| Bogdanski et al., 2012 (Poland) |
RCT, DB, Parallel | Obese, Hypertensive patients | M/F | 28/28 | 49.2 | 32.5 | 12 | Green Tea Extract (379 mg/day) = 208 mg EGCG Placebo |
CRP TNFα TAC |
| Suliburska et al., 2012 (Poland) |
RCT, DB, Parallel | Obese | M/F | 23/23 | 48.56 | 32.07 | 12 | EGCG (208 mg/day) Placebo (Microcrystalline Cellulose) |
TAC |
| Mousavi et al., 2013 (Iran) (a) |
RCT, Parallel | T2DM | M/F | 24/14 | 54.6 | 27.4 | 8 | Green Tea (10 g/day) = 800 ml Green Tea Drink Placebo |
TAC |
| MDA | |||||||||
| Mousavi et al., 2013 (Iran) (b) |
RCT, Parallel | T2DM | M/F | 25/14 | 54.6 | 27.4 | 8 | Green Tea (5 g/day) = 400 ml Green Tea Drink Placebo |
TAC MDA |
| Basu et al., 2013 (USA) (a) |
RCT, Parallel | MetS | M/F | 13-Dec | 42.8 | 34.6 | 8 | EGCG (440 mg/day – Brewed Green Tea) Placebo |
GPx |
| Basu et al., 2013 (USA) (b) |
RCT, Parallel | MetS | M/F | 10-Dec | 39.5 | 38 | 8 | EGCG (460 mg/day - Capsule) Placebo |
GPx |
| Lasaite et al., 2014 (Lithuania) |
RCT, DB, Parallel | T2DM | M/F | 17/14 | 57.2 | NR | 36 | Green Tea Extract (400 mg/day) Placebo (Microcrystalline cellulose) |
TAC |
| Spadiene et al., 2014 (Lithuania) (a) |
RCT, DB, Parallel | T2DM | M/F | 20/25 | 62.18 | NR | 36 | Green Tea Extract (400 mg/day) Placebo (Microcrystalline cellulose) |
TAC MDA GPx SOD |
| Spadiene et al., 2014 (Lithuania) (b) |
RCT, DB, Parallel | T2DM | M/F | 20/25 | 62.18 | NR | 36 | Green Tea Extract (400 mg/day) Placebo (Microcrystalline cellulose) |
TAC MDA GPx SOD |
| Liu et al., 2014 (Taiwan) |
RCT, DB, Parallel | T2DM | M/F | 39/38 | 55 | 26.2 | 16 | Decaffeinated Green Tea Extract (1500 mg/day) Placebo |
CRP |
| Mielgo-Ayuso et al., 2014 (Spain) |
RCT, DB, Parallel | Obese | F | 43/30 | 19-49 | NR | 12 | EGCG (300 mg/day) Placebo (Lactose) |
CRP |
| Kuo et al., 2015 (Taiwan) |
RCT, DB, Parallel | Healthy | M | 10-Oct | 20 | 21.95 | 4 | Green Tea Extract (250 mg/day) Placebo (Starch) | TAC MDA CRP |
| Borges et al., 2016 (Brazil) |
RCT, DB, Parallel | Diabetic Nephropathy | M/F | 21/21 | 43.2 | 24.6 | 12 | EGCG (800 mg/day) Placebo |
|
| Lee et al., 2016 (Taiwan) |
RCT, Parallel | Chronic Stable Angina | M/F | 35/36 | 62.6 | 25.3 | 6 | Green Tea Polyphenols (600 mg/day) Placebo |
CRP |
| Hussain et al., 2017 (Pakistan) |
RCT, Parallel | NAFLD | M/F | 40/40 | 25 | 29.5 | 12 | Green Tea Extract (1000 mg/day) Placebo |
CRP |
| Hadi et al., 2017 (Iran) |
RCT, DB, Parallel | Soccer Athletes | M | 16/16 | 20.94 | 22.6 | 6 | Green Tea Extract (450 mg/day) Placebo (Maltodextrin) |
TAC |
| Soeizi et al., 2017 (Iran) |
RCT, Parallel | β–thalassaemia major | M/F | 26/26 | 23.1 | 20.9 | 8 | Green Tea (7.5 g/day) Placebo |
TAC MDA |
| Tabatabaee et al., 2017 (Iran) |
RCT, DB, Parallel | NAFLD | M | 21/24 | 41 | 43.06 | 12 | Green Tea (550 mg/day) Placebo |
TAC MDA |
| Mombaini et al., 2017 (Iran) |
RCT, Parallel | PCOS | F | 22/23 | 23.22 | 28.96 | 6 | Green Tea (2000 mg/day) Placebo |
CRP TNFα IL-6 |
| Nogueira et al., 2017 (Brazil) |
RCT, Crossover | Obese prehypertensive women | F | 20/20 | 41.1 | 33.56 | 4 | Green Tea (1500 mg/day) Placebo (Cellulose) |
CRP TNFα IL-6 |
| Venkatakrishnanet al., 2018 (Taiwan) |
RCT, DB, Parallel | Healthy | M/F | 20/19 | 35-55 | 31.39 | 12 | Green Tea Catechins (780 mg/day) Placebo |
TAC GPx SOD |
| Shin et al., 2018 (South Korea) |
RCT, Parallel | Complete removal of colorectal adenomas by endoscopic polypectomy | M/F | 72/71 | 59.6 | 24.1 | 48 | Green Tea Extract (900 mg/day) Placebo |
CRP |
| Maeda-Yamamoto et al., 2018 (Japan) |
RCT, DB, Parallel | Healthy | M/F | 38/37 | 49.8 | 23.9 | 12 | EGCG (322 mg/day) Placebo |
SOD |
| Azizbeigi et al., 2019 (Iran) |
RCT, Parallel | Obese | M | 10-Oct | 23.9 | 31.8 | 8 | Green Tea (500 mg/day) + Training Placebo (Sucrose) + Training |
CRP TNFα IL-6 TAC MDA |
| Bagheri et al., 2020 (Iran) |
RCT, Parallel | Overweight | M | 15/15 | 43.8 | 27.3 | 8 | Green Tea (500 mg/day) + Training Placebo + Training |
CRP TNFα IL-6 |
| Benlloch et al., 2020 (Spain) |
RCT, Parallel | MS | M | 25/21 | 44.56 | 25.92 | 16 | EGCG (800 mg/day) Placebo |
CRP |
| Hadi et al., 2020 (Iran) |
RCT, DB, Parallel | T2DM | M/F | 22/22 | 51.47 | 29.44 | 8 | EGCG (300 mg/day) Placebo |
CRP TAC MDA |
| Kondori et al., 2021 (Iran) |
RCT, Parallel | Athletes | M | 12-Dec | 24.5 | 23.2 | 10 | Green Tea Extract (500 mg/day) + Exercise Placebo (Maltodextrin) + Exercise |
CRP TAC MDA |
| Bazyar et al., 2021 (Iran) |
RCT, DB, Parallel | T2DM | M/F | 22/22 | 51.75 | 29.46 | 8 | EGCG (300 mg/day) Placebo (White Flour) |
IL-6 TAC |
| El-Elimat et al., 2022 (Jordan) |
non-randomised open-label comparative study | Overweight and obese | M/F | 16/18 | 28 | 35.7 | 12 | Matcha Green Tea (2000 mg/day) Placebo |
IL-6 GPx |
| Naderifard al., 2022 (Iran) (a) |
RCT, Parallel | Untrained Women | F | 14/14 | 32.4 | 26.22 | 6 | Matcha Green Tea (1000 mg/day) Placebo (Dextrin) |
MDA GPx |
| Naderifard al., 2022 (Iran) (b) |
RCT, Parallel | Untrained Women | F | 14/14 | 32.4 | 26.22 | 6 | Matcha Green Tea (1000 mg/day) + Training Placebo (Dextrin) + Training |
MDA GPx |
| Rondanelli al., 2023 (Italy) |
RCT, DB, Parallel | Overweight or obese post-menopausal women | M/F | 14/14 | 60.57 | 31.1 | 8 | Green Tea Extract (300 mg/day) Placebo |
CRP |
| Ahmed Merza Mohammadet al., 2023 (Iraq) |
RCT, DB, Parallel | COVID | M/F | 26/24 | 50.1 | 27.11 | 4 | Green Tea Catechins (360 mg/day) Placebo |
TNFα IL-6 |
DB: Double-blind/NR: Not reported/T2DM: Type 2 diabetes mellitus/MetS: Metabolic syndrome/ PCOS: Polycystic ovary syndrome/NAFLD: Non-alcoholic fatty liver disease/MS: Multiple Sclerosis/M: male/F: female/CRP: C-reactive protein/TNF-a: Tumour necrosis factor-a/IL: Interleukin/TAC: Total antioxidant capacity/MDA: Malondialdehyde/GPx: Glutathione peroxidase/SOD: Superoxide dismutase.
Data presented in order of year.