Table 2. Relative risks for established colorectal cancer risk factors.
| Risk factors | Relative risk* |
|---|---|
| Factors associated with increased risk | |
| Hereditary and family history | |
| Family history | |
| • CRC | |
| 1 or more first-degree relatives | 2.2 |
| 1 or more first-degree relatives diagnoses before age 50 | 3.6 |
| 2 or more first-degree relatives | 4 |
| 1 or more second-degree relatives | 1.7 |
| • Adenoma | |
| 1 or more first-degree relatives | 2 |
| Inflammatory bowel disease | 1.3 |
| Type 2 diabetes | |
| Male | 1.4 |
| Female | 1.2 |
| Modifiable factors | |
| • Heavy alcohol (daily average >3 drinks) | 1.3 |
| • Obesity BMI ≥30 kg/m2) | 1.3 |
| Colon, male | 1.5 |
| Colon, female | 1.1 |
| Rectum, male | 1.3 |
| Rectum, female | 1.0Ƚ |
| • Red meat (100 g/day) | 1.1 |
| • Processed meat (50 g/day) | 1.2 |
| Smoking (ever vs. never) | |
| Factors associated with decreased risk: | |
| Physical activity | 0.7 |
| Dairy (400 g/day) | 0.9 |
*, relative risk compares the risk of disease among people with a particular “exposure” to the risk among people without that exposure. Relative risk for dietary factors compares the highest with the lowest consumption. If the relative risk is more than 1.0, then risk is higher among exposed than unexposed persons. Relative risks less than 1.0 indicate a protective effect; Ƚ, relative risk was not statistically significant. Produced with permission: Modified from (1). ©2020 American Cancer Society, Inc., Surveillance Research. CRC, colorectal cancer.