Table 2.
Investigation on the effect of tea drinking on the risk of cancer in humans*
| Position | Tea | Cohort study |
Case study |
||
| Risk decreased | Risk not decreased | Risk decreased | Risk not decreased | ||
| Colon | Green tea | 2 | 5 | 4 | 3 |
| Black tea | 2 | 8 | 4 | 12 | |
| Lung | Green tea | 0 | 3 | 2 | 3 |
| Black tea | 0 | 8 | 6 | 4 | |
| Stomach | Green tea | 2 | 6 | 8 | 8 |
| Black tea | 0 | 6 | 4 | 5 | |
| Esophagous | Green tea | 0 | 2 | 3 | 4 |
| Black tea | 0 | 1 | 2 | 1 | |
| Mammary gland | Green tea | 3 | 4 | 3 | 0 |
| Black tea | 1 | 8 | 1 | 9 | |
| Prostate | Green tea | 2 | 0 | 2 | 0 |
| Black tea | 1 | 2 | 1 | 3 | |
| Ovary | Green tea | 1 | 0 | 1 | 0 |
| Black tea | 2 | 3 | 0 | 6 | |
| Pancreas | Green tea | 0 | 2 | 1 | 1 |
| Black tea | 0 | 4 | 1 | 3 | |
| Kidney and bladder | Green tea | 0 | 1 | 0 | 4 |
| Black tea | 1 | 4 | 2 | 5 | |
| Others | Green tea | 0 | 2 | 5 | 1 |
| Black tea | 2 | 3 | 1 | 3 | |
*
From 1965–2008 animal model information from PubMed Medline
Adapted with permission from Macmillan Publishers Ltd.: Nat. Rev. Cancer (Yang et al., 2009), copyright 2009