The investigators evaluated the effect of fruit and vegetable intake on the risk of developing adenomatous polyps.
The findings of the study were published in the American Journal of Epidemiology.
High vegetable intakes have been associated with a lower risk of colorectal cancer. However, this relation is less well established for the precursor lesions, adenomatous polyps.
A total of 564 patients with adenomatous polyps were included in the study. In addition, 682 colonoscopy-negative controls (who were polyp-free at colonoscopy) and 535 community controls were studied.
Dietary intake was assessed using a food frequency questionnaire.
| Juice consumption reduced adenoma risk in women.
| American Journal of Epidemiology |
For women, adenoma risk was approximately halved in the highest versus lowest quintile of juice consumption.
The association was stronger for adenomas with moderate or severe dysplasia, compared with mild dysplasia.
The authors found that juice was not associated with adenoma risk in men.
The results for fruits, vegetables, total fruits and vegetables, green leafy vegetables, and several botanically and phytochemically defined subgroups generally were not statistically significant.
Stephanie A. Smith-Warner, of the University of Minnesota, Minneapolis, concluded on behalf of her colleagues, "As elevated vegetable consumption has been associated with a lower risk of colorectal cancer, vegetables may have a stronger role in preventing the progression of adenomas to carcinomas, rather than in preventing the initial appearance of adenomas."