Table 1 Associations between milk consumption and cancer outcomes
Outcomes | First author | Year | Types of milk | No. of studies in MA | Type of studies in MA | No. of cases/total | Effects mode | Metric of MA | Effect size | 95% CI | I2% | Publication bias |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Significant associations | ||||||||||||
Most beneficial | ||||||||||||
Colon cancer | Barrubes | 2019 | Low-fat milk | 2 | Cohort | 3339/15,441 | Fixed | RR | 0.73 | 0.61–0.87 | 0 | NA |
Distal colon cancer | Barrubes | 2019 | Milk | 3 | Cohort | 40,651/15,657 | Fixed | RR | 0.75 | 0.63–0.90 | 25 | NA |
CRC | Barrubes | 2019 | Low-fat milk | 2 | Cohort | 3507/484,338 | Fixed | RR | 0.76 | 0.66–0.88 | 42 | NA |
Colon cancer | Barrubes | 2019 | Milk | 8 | Cohort | 3339/15,441 | Random | RR | 0.79 | 0.72–0.87 | 0 | NA |
Proximal colon cancer | Barrubes | 2019 | Milk | 3 | Cohort | 40,651/15,657 | Fixed | RR | 0.81 | 0.68–0.96 | 0 | NA |
CRC | Barrubes | 2019 | Milk | 9 | Cohort | 9118/1,003,303 | Random | RR | 0.82 | 0.76–0.88 | 2 | NA |
Rectal cancer | Barrubes | 2019 | Milk | 5 | Cohort | NA | Random | RR | 0.84 | 0.73–0.97 | 0 | NA |
Colon cancer | Barrubes | 2019 | Milk | 3 | Cohort | 3339/15,441 | Fixed | RRa | 0.88 | 0.84–0.93 | 0 | NA |
Bladder Cancer | Bermejo | 2019 | Milk | 14 | Cohort/case control | NA/438,319 | Random | RR | 0.89 | 0.81–0.98 | 66.4 | 0.269 |
CRC | Barrubes | 2019 | Milk | 9 | Cohort | 9118/1,003,303 | Random | RRb | 0.90 | 0.86–0.93 | 0 | NA |
Rectal cancer | Barrubes | 2019 | Milk | 3 | Cohort | NA | Fixed | RRc | 0.91 | 0.84–0.97 | 25 | NA |
Prostate cancer | Aune | 2015 | Milk | 8 | Cohort | 19,664/448,719 | Random | RR | 0.92 | 0.85–0.99 | 0 | No |
Breast cancer | Wu | 2016 | Skim milk | 8 | Cohort | 16,664/586,726 | Random | RR | 0.93 | 0.85–1.00 | 40.1 | 0.616 |
Breast cancer | Wu | 2016 | Skim milk | 5 | Cohort | NA | Random | RR | 0.96 | 0.92–1.00 | 11.9 | 0.498 |
Most harmful | ||||||||||||
DLBCL | Wang | 2016 | Milk | 3 | Case–control | 352/NA | Random | RR | 1.49 | 1.08–2.06 | 8.9 | NA |
Gastric cancr | Wang | 2018 | Milk | 21 | Cohort/case control | NA | Random | RR | 1.44 | 1.15–1.81 | 82.7 | NA |
NHL | Wang | 2016 | Milk | 14 | Cohort/case control | 7109/NA | Random | RR | 1.41 | 1.08–1.84 | 88.6 | no |
Ovarian cancer | Liu | 2015 | Milk | 11 | Cohort | NA | Random | OR | 1.23 | 1.03–1.46 |  > 50 | 0.957 |
Bladder Cancer | Bermejo | 2019 | Milk | 3 | Cohort/case control | NA/3933 | Random | RR | 1.21 | 1.04–1.38 | 86.1 | NA |
Prostate cancer | Aune | 2015 | Low-fat milk | 6 | Cohort | 19,430/432,943 | Random | RRd | 1.14 | 1.05–1.25 | 51 | NA |
NHL | Wang | 2016 | Milk | 9 | Cohort/case control | 3739/NA | Random | RRe | 1.13 | 1.00–1.28 | NA | NA |
NHL | Wang | 2016 | Milk | 9 | Cohort/case control | 3739/NA | Random | RRf | 1.12 | 1.00–1.26 | NA | NA |
Prostate cancer | Aune | 2015 | Milk | 14 | Cohort | 11,392/566,146 | Random | RR | 1.11 | 1.03–1.21 | 21 | no |
Prostate cancer | Aune | 2015 | Low-fat milk | 5 | Cohort | NA/374,664 | Random | RRg | 1.06 | 1.01–1.11 | 67 | NA |
Prostate cancer | Aune | 2015 | Milk | 13 | Cohort | NA/559,383 | Random | RRg | 1.03 | 1.00–1.06 | 9 | NA |
Non-significant associations | ||||||||||||
Distal colon cancer | Barrubes | 2019 | Milk | 2 | Cohort | 40,651/15,657 | Fixed | RR | 0.78 | 0.60–1.01 | 0 | NA |
Breast cancer | Chen | 2019 | Low-fat milk | 3 | Case–control | NA | Random | OR | 0.85 | 0.70–1.04 |  < 50 | 0.583 |
Colon cancer | Barrubes | 2019 | Milk | 2 | Cohort | 3339/15,441 | Fixed | RR | 0.87 | 0.72–1.05 | 0 | NA |
Pancreatic cancer | Genkinger | 2014 | Low-fat milk | 14 | Cohort | 307/NA | Random | HR | 0.87 | 0.75–1.01 | 5 | NA |
Breast cancer | Wu | 2016 | Milk | 18 | Cohort | 19,747/775,778 | Random | RR | 0.92 | 0.84–1.02 | 53.5 | 0.292 |
Pancreatic cancer | Genkinger | 2014 | Milk | 14 | Cohort | 373/NA | Random | HR | 0.92 | 0.77–1.10 | 0 | NA |
Ovarian cancer | Liu | 2015 | Low-fat/skim milk | 13 | Cohort | NA | Random | OR | 0.93 | 0.79–1.09 |  < 50 | 0.370 |
ESCC | Li | 2016 | Milk | 11 | Case–control | 2311/NA | Random | RR | 0.93 | 0.74–1.16 | 52.9 | 0.960 |
Rectal cancer | Barrubes | 2019 | Milk | 2 | Cohort | NA | Fixed | RR | 0.94 | 0.76–1.16 | 0 | NA |
Breast cancer | Chen | 2019 | Milk | 8 | Case–control | NA | Random | OR | 0.95 | 0.80–1.13 |  < 50 | 0.272 |
CRC | Barrubes | 2019 | Milk | 3 | Cohort | 5198/545,046 | Fixed | RR | 0.97 | 0.86–1.09 | 40 | NA |
Breast cancer | Wu | 2016 | Milk | 11 | Cohort | NA | Random | RRg | 0.97 | 0.93–1.01 | 36.4 | 0.355 |
ESCC | Li | 2016 | Milk | 6 | Case–control | NA | Random | RRb | 0.97 | 0.70–1.35 | 58.9 | NA |
Lung cancer | Yang | 2016 | Low-fat milk | 3 | Cohort/case control | NA | Random | RR | 0.98 | 0.69–1.41 | 0 | 0.120 |
Prostate cancer | Aune | 2015 | Milk | 6 | Cohort | NA/388,664 | Random | RRg | 0.98 | 0.95–1.01 | 0 | NA |
NHL | Sergentanis | 2019 | Milk | 4 | Cohort | 1517/NA | Random | RR | 0.99 | 0.85–1.15 | 0 | 0.461 |
Breast cancer | Wu | 2016 | Milk | 9 | Cohort | 13,781/554,775 | Random | RR | 0.99 | 0.87–1.12 | 37.4 | 0.723 |
Endometrial cancer | Li | 2017 | Milk | 6 | Cohort/case control | 3538/331,168 | Random | OR | 0.99 | 0.89–1.10 | 0 | NA |
FL | Wang | 2016 | Milk | 3 | Case–control | 390/NA | Random | RR | 0.99 | 0.47–2.07 | 89.8 | NA |
Pancreatic cancer | Genkinger | 2014 | Milk | 14 | Cohort | 145/NA | Random | HR | 1.01 | 0.83–1.22 | 0 | NA |
Breast cancer | Wu | 2016 | Milk | 5 | Cohort | NA | Random | RRg | 1.02 | 0.92–1.13 | 32.8 | 0.660 |
NHL | Wang | 2016 | Milk | 9 | Cohort/case control | 3739/NA | Random | RRh | 1.04 | 0.97–1.12 | NA | NA |
SLL/CLL | Wang | 2016 | Milk | 3 | Case–control | 477/NA | Random | RR | 1.04 | 0.69–1.55 | 44.1 | NA |
NHL | Wang | 2016 | Milk | 9 | Cohort/case control | 3739/NA | Random | RRi | 1.07 | 0.96–1.19 | NA | NA |
Lung cancer | Yang | 2016 | Milk | 22 | Cohort/case control | NA | Random | RR | 1.08 | 0.80–1.46 | 90.5 | 0.300 |
NHL | Wang | 2016 | Milk | 9 | Cohort/case control | 3739/NA | Random | RRj | 1.11 | 0.99–1.24 | NA | NA |
HCC | Yang | 2017 | Milk | 7 | Cohort/case control | NA | Random | RR | 1.13 | 0.67–1.88 | 78 | > 0.1 |
Proximal colon cancer | Barrubes | 2019 | Milk | 2 | Cohort | 40,651/15,657 | Fixed | RR | 1.20 | 0.96–1.49 | 83 | NA |