Table 4.
Characteristics of studies of fruit and vegetables and CRC
| Study | Number of study participants | Age of participants | Follow-up years | CRC incidence | Analytic category | Analytical comparison, high versus low intake | Relative risk (95% CI) | Ref |
|---|---|---|---|---|---|---|---|---|
| EPIC | 131,985 men and 320,770 women | 35–70 | 1992–2006 | 2, 819 (CRC) | Fruit and vegetables | >603.6 g/day versus <221.1 g/day | CRC: 0.86 (0.75–1.00), p= 0.04 | Ref (55, 71) |
| NIH-AARP DHS | 291,094 men and 196,949 women | 50–71 | 1995–2000 | 2,972 (CRC) | Vegetables | Men: >2.8 servings/1000 kcal versus <0.6 servings/1000 kcal | Men-CRC: 0.82 (0.71–0.94), p=0.03 | Ref (74) |
| Men-Distal colon cancer: 0.76 (0.59–0.98), p=0.04 | ||||||||
| Fruit | Women: >3.5 servings/1000 kcal versus <0.6 servings/1000 kcal | Women-Rectal cancer: 1.59(1.04–2.44), p=0.01 | ||||||
| Green leafy vegetables | – | Men-CRC: 0.86 (0.74–0.99), p=0.04 | ||||||
| 19 prospective studies | – | – | – | – | Fruit and vegetables | – | CRC: 0.92 (0.86 – 0.99) | Ref (79) |
| 24 case–control and 11 prospective studies | 1,295,063 men and women | 1978–2012 | 24,275 (CRC) | Cruciferous vegetable | – | CRC: 0.82 (0.75–0.90) | Ref (81) | |
| EPIC | 477,312 men and women | 35–70 | 1992–2006 | 2,869 (Colon), 1,648 (Rectrum) | Total flavonoids and flavonoid | – | non-significant associations | Ref (72) |
| HPFS and NHS | 42,478 men and 76,364 women | 40–75/30–55 | 1986–2010/1980–2010 | 2,519 (CRC) | Flavonoid | – | non-significant associations | Ref (73) |
| NLCS–MIC | 58,279 men and 62,573 women | 55–69 | 1986–2000 | 1,678 (Colon), 572 (Rectum) | Total flavonol and flavone | – | non-significant associations | Ref (75) |
| Case-control | – | 40–79 | – | 834 (CRC), 939 (Control) | Fruit and vegetables | >10.82 servings/day versus <5.77 servings/day | non-significant associations | Ref (77) |
| 6 cohorts and 11 case–control | – | – | – | – | Fruit and vegetables | – | non-significant associations | Ref (78) |
| 14 cohort studies | 756,217 men and women | – | 6 to 20 years | 5,383 (Colon) | Fruit and vegetables | – | non-significant associations | Ref (80) |
| 6 cohorts | 686,629 men and women | – | – | 4,062 (CRC) | Semi-vegetarian diet | Versus non-vegetarian diet | CRC: 0.86 (0.79–0.94) | Ref (83) |
| Pesco-vegetarian diet | Versus non-vegetarian diet | CRC: 0.67 (0.53–0.83) | ||||||
| AHS II | 77,659 men and women | – | 2002–2009 | 380 (Colon), 110 (Rectum) | Vegetarian diet | Versus non-vegetarian diet | CRC: 0.78 (0.64-0.95), p=0.01 | Ref (82) |
| Pesco-vegetarian diet | Versus non-vegetarian diet | CRC: 0.57 (0.40–0.82), p=0.002 | ||||||
| EPIC-Oxford | 12,230 men and 40,476 women | 20–89 | 1993–2005 | 290 (CRC) | Vegetarian | Versus non-vegetarian | CRC: 1.49 (1.09–2.03) | Ref (84) |
| Vegetarian or vegan | Versus meat-eater | CRC: 1.39 (1.01–1.91) |