Case Control Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 14, 2017; 23(14): 2527-2538
Published online Apr 14, 2017. doi: 10.3748/wjg.v23.i14.2527
Colors of vegetables and fruits and the risks of colorectal cancer
Jeeyoo Lee, Aesun Shin, Jae Hwan Oh, Jeongseon Kim
Jeeyoo Lee, Aesun Shin, Department of Preventive Medicine, Seoul National University College of Medicine, Seoul 03080, South Korea
Jae Hwan Oh, Center for Colorectal Cancer, National Cancer Center, Goyang-si 10408, South Korea
Jeongseon Kim, Molecular Epidemiology Branch, Division of Cancer Epidemiology and Prevention, Research Institute, National Cancer Center, Goyang-si 10408, South Korea
Author contributions: Shin A and Kim J contributed equally to this manuscript, and considered to be the co-corresponding authors; Lee J performed the statistical analysis and drafted the manuscript; Shin A and Kim J advised the statistical analysis and helped to draft the manuscript; Shin A, Oh JH and Kim J conceived of the study and reviewed, guided, and edited the manuscript; all authors approved the final manuscript.
Supported by the National Research Foundation of Korea, No. 2010-0010276 and No. 2013R1A1A2A10008260; and the National Cancer Center, Korea, No. 0910220 and No. 1210141.
Institutional review board statement: The study protocol was approved by the Institutional Review Board of the National Cancer Center (IRB No. NCCNCS-10-350 and NCC2015-0202).
Informed consent statement: All patients gave informed consent.
Conflict-of-interest statement: No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at and
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Correspondence to: Jeongseon Kim, PhD, Molecular Epidemiology Branch, Division of Cancer Epidemiology and Prevention, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang-si 10408, South Korea.
Telephone: +82-31-9202570 Fax: +82-31-9202579
Received: November 17, 2016
Peer-review started: November 18, 2016
First decision: January 10, 2017
Revised: February 20, 2017
Accepted: March 20, 2017
Article in press: March 20, 2017
Published online: April 14, 2017

To investigate the relationship between the colors of vegetables and fruits and the risk of colorectal cancer in Korea.


A case-control study was conducted with 923 colorectal cancer patients and 1846 controls recruited from the National Cancer Center in Korea. We classified vegetables and fruits into four groups according to the color of their edible parts (e.g., green, orange/yellow, red/purple and white). Vegetable and fruit intake level was classified by sex-specific tertile of the control group. Logistic regression models were used for estimating the odds ratios (OR) and their 95% confidence intervals (CI).


High total intake of vegetables and fruits was strongly associated with a reduced risk of colorectal cancer in women (OR = 0.32, 95%CI: 0.21-0.48 for highest vs lowest tertile) and a similar inverse association was observed for men (OR = 0.60, 95%CI: 0.45-0.79). In the analysis of color groups, adjusted ORs (95%CI) comparing the highest to the lowest of the vegetables and fruits intake were 0.49 (0.36-0.65) for green, and 0.47 (0.35-0.63) for white vegetables and fruits in men. An inverse association was also found in women for green, red/purple and white vegetables and fruits. However, in men, orange/yellow vegetables and fruits (citrus fruits, carrot, pumpkin, peach, persimmon, ginger) intake was linked to an increased risk of colorectal cancer (OR = 1.61, 95%CI: 1.22-2.12).


Vegetables and fruits intake from various color groups may protect against colorectal cancer.

Keywords: Vegetable and fruits, Colorectal cancer, Korea

Core tip: Although many studies have focused on the associations between vegetable and fruit intake and health, few studies have classified vegetables and fruits by their colors, which reflect their unique contents of phytochemicals and micronutrients. In the current study, most color groups of vegetables and fruits showed protective benefits against colorectal cancer regardless of the anatomical subsites.