TABLE 2.
Characteristics of all eligible studies
| First author, publication year | Location | Age | Sample size | BMI | Subjects | Type of study | Intervention | Duration | outcomes |
|---|---|---|---|---|---|---|---|---|---|
| Kyung Hui (2007) | Korea | 47.1 | 43 | 25.6 | Patients with hypercholesterolemia | Randomized placebo‐controlled parallel trial | 200 ml/day onion extract | 8 weeks | TG, TC, HDL, LDL |
| Lee (2010) | Korea | 45.9 | 27 | 24.6 | borderline hypercholesterolemic subjects | Randomized single blind placebo‐controlled crossover trial | 150 ml/day onion extract | 10 weeks | TG, TC, HDL, LDL |
| Lee (2011) | Korea | 44.4 | 92 | 24.9 | Healthy male smokers | Randomized, Double blinded placebo‐controlled parallel trial | 1,000 mg/day OPE | 10 weeks | TG, TC, HDL, LDL |
| Kim (2013) | Korea | N | 12 | 20.2 | healthy young women | Randomized double‐blind placebo‐controlled crossover trial | 1,000 mg/day OPE | 2 weeks | TG, HDL, LDL |
| Kim (2015) | Korea | 45 | 37 | 26.3 | Obese women | Randomized double‐blind placebo controlled parallel trial | 100 mg/day OPE | 12 weeks | TG, TC, HDL, LDL |
| Choi (2015) | Korea | 43.1 | 62 | 26.2 | Overweight and obese subjects | Randomized double‐blind placebo‐controlled parallel trial | 1,000 mg/day OPE | 12 weeks | TG, TC, HDL, LDL |
| Lu (2015) | China | N | 23 | 25.2 | Mild hypercholesterolemic adults | Randomized placebo‐controlled parallel trial | 100 ml/day onion juice | 8 weeks | TG, TC, HDL, LDL |
| Brüll (2016) | Germany | 48.1 | 22 | 30.9 | Overweight‐to‐obese adults with hypertension | Randomized double‐blinded placebo‐controlled crossover trial | 396 mg/day OPE | 6 weeks | TG, TC, HDL, LDL |
| Park (2016) | Korea | 43.3 | 72 | 26.6 | Overweight and obese subjects | Randomized double‐blind, placebo‐controlled parallel trial | 340 mg/day OPE | 12 weeks | TG, TC, HDL, LDL |
| Jeong (2019) | Korea | 42.0 | 56 | 27.2 | Overweight Subjects | Randomized double‐blind placebo‐controlled parallel trial | 900 mg/day steamed onion | 12 weeks | TG, TC, HDL, LDL |
Abbreviations: HDL, high‐density lipoprotein cholesterol; LDL, low‐density lipoprotein cholesterol; N, not available; OPE, onion peel extract; TG, Triglyceride; TC, total cholesterol.