Table 1.
Associations between allium vegetables consumption and cancer and tumor outcomes
| Outcome | Author | Year | Type of allium vegetables | Population | Type of studies in MA | No. of studies and participants in MA | Metric of MA | Effects model | Effect size (95% CI) | I 2%a | Publication biasb |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Gastric cancer | Li, Z. Y., et al | 2018 | Garlic or garlic powder | Participants from Asia, Europe, and America | 1 interventional study, 2 cohort, and 15 case–control studies | 18; 142,921 | OR | REM | 0.51 (0.44, 0.57) | 59.6 | 0.9 |
| Gastric cancer | Turati, F., et al | 2015 | Onion | Participants from Asia, Europe, and South America | 13 case–control studies | 13; 4,619 | RR | REM | 0.55 (0.41, 0.73) | 76.0 | 0.04 |
| Gastric cancer | Turati, F., et al | 2015 | Chinese chives | Participants from Asia, Europe, and South America | 3 case–control studies | 3; 1,595 | RR | REM | 0.43 (0.26, 0.73) | 70.9 | None |
| Gastric cancer | Turati, F., et al | 2015 | Allium vegetables | Participants from Asia, Europe, and South America | 4 cohort and 10 case–control studies | 14; 6,227 | RR | REM | 0.78 (0.67, 0.91) | 58.6 | None |
| Colorectal cancer | Chiavarini, M., et al | 2016 | Garlic or garlic supplement | Participants from China, Europe, Argentina and America | 7 cohort and 7 case–control studies | 14; 535,901 | OR | REM | 0.93 (0.82, 1.06) | 83.6 | 0.121 |
| Colorectal cancer | Turati, F., et al | 2014 | Onion | Participants from Asia, Europe, Australia, and North and South America | 2 cohort and 4 case–control studies | 6; NR | RR | REM | 0.85 (0.7, 1.04) | 46.1 | 0.106 |
| Colorectal cancer | Zhu, B. B., et al | 2014 | Allium vegetables | Participants from China, the Netherlands, and America | Observational studies | 8; 552,180 | RR | FEM | 1.06 (0.96, 1.17) | 0 | 0.35 |
| Colorectal cancer of male | Chiavarini, M., et al | 2016 | Garlic or garlic supplement | Participants from China, Europe, Argentina, and America | 3 cohort and 1 case–control studies | 4; 141,341 | OR | REM | 1.02 (0.89, 1.18) | 0 | 0.848 |
| Colorectal cancer of female | Chiavarini, M., et al | 2016 | Garlic or garlic supplement | Participants from China, Europe, Argentina, and America | 3 cohort and 2 case–control studies | 5; 115,784 | OR | REM | 0.94 (0.79, 1.12) | 54.9 | 0.005 |
| Colon cancer | Chiavarini, M., et al | 2016 | Garlic or garlic supplement | Participants from China, Europe, Argentina, and America | 5 cohort and 1 case–control studies | 6; 200,711 | OR | REM | 0.93 (0.74, 1.16) | 71.1 | 0.026 |
| Rectal cancer | Chiavarini, M., et al | 2016 | Garlic or garlic supplement | Participants from China, Europe, Argentina, and America | 2 cohort and 1 case–control studies | 3; 91,368 | OR | REM | 1.00 (0.69, 1.45) | 41.4 | 0.061 |
| Colorectal adenomatous polyps | Turati, F., et al | 2014 | Allium vegetables | Participants from America | Case–control studies | 3; NR | RR | FEM | 0.88 (0.80, 0.98) | 0 | 0.756 |
| Upper aerodigestive tract cancer | Guercio, V., et al | 2016 | Allium vegetables | Worldwide countries | 3 cohort and 4 case–control studies | 7; 368,435 | RR | REM | 0.79 (0.56, 1.11) | 76.5 | None |
| Upper aerodigestive tract cancer | Guercio, V., et al | 2016 | Garlic | Worldwide countries | 10 case–control studies | 10; 22,660 | RR | REM | 0.74 (0.57, 0.95) | 76.9 | None |
| Upper aerodigestive tract cancer | Guercio, V., et al | 2016 | Onion | Worldwide countries | 1 cohort and 7 case–control studies | 8; 19,229 | RR | REM | 0.72 (0.57, 0.91) | 60.6 | None |
| Esophagus cancer | Guercio, V., et al | 2016 | Allium vegetables | Worldwide countries | Observational studies | 4; NR | RR | REM | 0.65 (0.31, 1.35) | NR | NR |
| Esophagus cancer | Guercio, V., et al | 2016 | Garlic | Worldwide countries | Observational studies | 8; NR | RR | REM | 0.68 (0.50, 0.92) | NR | NR |
| Esophagus cancer | Guercio, V., et al | 2016 | Onion | Worldwide countries | Observational studies | 5; NR | RR | REM | 0.66 (0.45, 0.97) | NR | NR |
| Head and neck cancer | Guercio, V., et al | 2016 | Garlic | Worldwide countries | Observational studies | 3; NR | RR | REM | 0.95 (0.57, 1.57) | NR | NR |
| Head and neck cancer | Guercio, V., et al | 2016 | Onion | Worldwide countries | Observational studies | 3; NR | RR | REM | 0.78 (0.57, 1.05) | NR | NR |
| Larynx cancer | Guercio, V., et al | 2016 | Onion | Worldwide countries | Observational studies | 3; NR | RR | REM | 0.72 (0.53, 0.97) | NR | NR |
| Prostate cancer | Zhou, X. F., et al | 2013 | Garlic | Participants from Asia, Europe, Australia, and America | 2 cohort and 5 case–control studies | 7; 68,600 | OR | REM | 0.77 (0.64, 0.91) | 63.6 | 0.015 |
| Prostate cancer | Zhou, X. F., et al | 2013 | Onion | Participants from Asia, Europe, Australia, and America | 1 cohort and 3 case–control studies | 4; 33,470 | OR | FEM | 0.84 (0.62, 1.13) | 49.4 | 0.015 |
95% CI, 95% confidence intervals; FEM, fixed effects model; NR, not reported; MA, meta‐analysis; OR, odds ratios; REM, random effects model; RR, relative risk.
a
Heterogeneity was assessed with I 2 statistic.
b
Assessed by Egger's regression test.