Case Control Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jun 28, 2018; 24(24): 2617-2627
Published online Jun 28, 2018. doi: 10.3748/wjg.v24.i24.2617
Mediterranean dietary components are inversely associated with advanced colorectal polyps: A case-control study
Naomi Fliss-Isakov, Revital Kariv, Muriel Webb, Dana Ivancovsky, Dana Margalit, Shira Zelber-Sagi
Naomi Fliss-Isakov, Revital Kariv, Muriel Webb, Shira Zelber-Sagi, Department of Gastroenterology Tel Aviv Medical Center, Tel Aviv 6423906, Israel
Naomi Fliss-Isakov, Revital Kariv, Muriel Webb, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6423906, Israel
Dana Ivancovsky, Dana Margalit, Shira Zelber-Sagi, School of Public Health, University of Haifa, Haifa 3498838, Israel
Author contributions: Fliss-Isakov N and Kariv R equally contributed to the paper; Fliss-Isakov N, Kariv R and Zelber-Sagi S conceived and designed the study; Fliss-Isakov N, Webb M, Ivancovsky D and Margalit M performed the data collection; Fliss-Isakov N, Kariv R and Zelber-Sagi S wrote the manuscript; Zelber-Sagi S critically reviewed the manuscript.
Institutional review board statement: The study was approved by the institutional review board of the Tel Aviv Medical Center.
Informed consent statement: All participants signed an informed consent.
Conflict-of-interest statement: None.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
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: Naomi Fliss-Isakov, PhD, Research Scientist, Department of Gastroenterology, Tel-Aviv Medical Center, 6 Weizmann Street, Tel-Aviv 64239, Israel.
Telephone: +972-3-6947305 Fax: +972-3-6974868
Received: March 30, 2018
Peer-review started: March 30, 2018
First decision: April 19, 2018
Revised: May 8, 2018
Accepted: May 18, 2018
Article in press: May 18, 2018
Published online: June 28, 2018

To evaluate the association between the Mediterranean diet (MD) pattern and its components, and advanced colorectal polyps (adenoma and serrated adenoma).


A case-control study among patients undergoing screening, diagnostic or surveillance colonoscopies during 2010-2015 at the Tel-Aviv Medical Center, Gastroenterology Department. Cases with advanced polyps were defined as: Advanced adenoma [> 10 mm, with features of high grade dysplasia (HGD) or villous histology], advanced serrated adenoma (> 10 mm or with dysplasia) or multiple (≥ 3) non-advanced adenomas or serrated adenomas. Cases of non-advanced adenomas were defined as adenomas < 10 mm, without features of HGD or villous histology. Controls were defined as those without polyps at the current colonoscopy and without a history of colorectal polyps. Data collection included: anthropometrics measured according to a standardized protocol, fasting blood tests performed at the same lab, medical history recorded by a structured interview and dietary intake evaluated by a 116-item food frequency questionnaire. Adherence to the MD components was evaluated according to intake above/below the sample median, for potentially beneficial/detrimental components respectively, as accepted.


We recruited 206 cases with advanced polyps, 192 cases with non-advanced adenoma and 385 controls. The number of adhered MD components was inversely associated with a diagnosis of advanced polyps in a dose-response manner (OR = 0.34, 95%CI: 0.17-0.65; OR = 0.22, 95%CI: 0.11-0.43; and OR = 0.18, 95%CI: 0.07-0.47 for 3-4, 5-7 and 8-10 components, respectively), but not with non-advanced adenomas (OR = 0.54, 95%CI: 0.25-1.13; OR = 0.48, 95%CI: 0.23-0.99; and OR = 0.43, 95%CI: 0.16-1.12 for 3-4, 5-7 and 8-10 components, respectively). Low intake of sugar-sweetened beverages and red meat, as well as high intake of fish, were inversely associated with advanced polyps (OR = 0.56, 95%CI: 0.36-0.87; OR = 0.63, 95%CI: 0.42-0.95; and OR = 0.66, 95%CI: 0.44-0.99, respectively), while only low intake of red meat was inversely associated with non-advanced adenomas (OR = 0.71, 95%CI: 0.49-0.97).


A better adherence to the MD, specifically low intake of sugar-sweetened beverages and red meat as well as high intake of fish, is related to lower odds for advanced polyps.

Keywords: Fish intake, Sugar-sweetened beverages, Red meat intake, Dietary adherence, Cancer

Core tip: Adherence to the Mediterranean diet is inversely associated with advanced colorectal polyps in a dose-response manner. Low intake of sugar-sweetened beverages and red meat, as well as high intake of fish, were associated with lower odds of advanced colorectal polyps. Importantly, these protective associations were independent of other important risk factors such as medical background and other lifestyle parameters. Therefore, a healthy diet may have a significant preventive role in colorectal neoplasia.