Intake Of Vegetable And Fruit By Colors And Risk Of Colorectal Cancer

Jeeyoo LEE, Seoul National University College of Medicine, South Korea
SHIN A. 1,2 , OH J. 3 , KIM J. 4

1 Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
2 Department of Nutritional Science and Food Management, Ewha Womans University, Seoul 120-750, Republic of Korea
3 Center for Colorectal Cancer, National Cancer Center, Goyang-si, Republic of Korea
4 Molecular Epidemiology Branch, Research Institute, National Cancer Center, Goyang-si, Republic of Korea

Purpose
The colors of vegetable and fruit reflect their contents of unique phytochemicals and micronutrients which may contribute to health promotion. In this case-control study, we aimed to investigate the relationship between vegetable and fruit classified by color and colorectal cancer risk.
Methods
A case-control study was conducted with 923 colorectal cancer patients and 1846 controls recruited from the National Cancer Center in Korea. Information on dietary intake was collected using a food frequency questionnaire (FFQ) with 106 items. We classified vegetable and fruit into four groups by the color of their mainly edible part (eg, green, orange/yellow, red/purple and white). Vegetable and fruit intake level was classified by sex-specific tertile of control group. Residual method was used to adjust total energy intake. Binary and polytomous logistic regression models were used to estimate odds ratios and their 95% confidence intervals.  
Results
High intake of total vegetable and fruit was strongly associated with a reduced risk of colorectal cancer in women (OR, 0.30; 95% CI 0.20-0.47 for highest vs. lowest tertile) and similar inverse association was observed for men (OR, 0.54; 95% CI 0.40-0.72). In color groups analysis, adjusted ORs (95% CI) comparing the highest vs. the lowest tertile of vegetable and fruit intake were: 0.47 (0.35-0.63) for green, and 0.50 (0.37-0.67) for white vegetable and fruit in men. An inverse association was also found in women for green (0.33 (0.21-0.51)), orange/yellow (0.65 (0.43-0.99)), red/purple (0.64 (0.43-0.96)) and white (0.29 (0.18-0.45)) vegetable and fruit.
Conclusion
We found a reduced risk of colorectal cancer among those with higher intake of vegetable and fruit of green or white as well as total intake amount in both men and women. 
​funding source
the National Research Foundation of Korea (2010–0010276 and 2013R1A1A2A10008260) and National Cancer Center Korea (0910220 and 1210141).