Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 7, 2015; 21(17): 5191-5209
Published online May 7, 2015. doi: 10.3748/wjg.v21.i17.5191
Role of vitamins in gastrointestinal diseases
Omar A Masri, Jean M Chalhoub, Ala I Sharara
Omar A Masri, Jean M Chalhoub, Ala I Sharara, Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut 11-0236, Lebanon
Author contributions: Masri OA performed research, completed the review, drafted the manuscript and prepared the tables; Masri OA, Chalhoub JM and Sharara AI interpreted the data and critically reviewed the manuscript; Masri OA and Chalhoub JM did the final editing of the manuscript; Chalhoub JM executed the figures, and managed references; Sharara AI designed the research.
Conflict-of-interest: No potential conflicts of interest relevant to this article were reported.
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: Ala I Sharara, MD, FACG, AGAF, Professor, Head, Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Cairo Street, Beirut 11-0236, Lebanon.
Telephone: +961-1-35000 Fax: +961-1-366098
Received: January 8, 2015
Peer-review started: January 9, 2015
First decision: February 10, 2015
Revised: February 23, 2015
Accepted: March 31, 2015
Article in press: March 31, 2015
Published online: May 7, 2015
Processing time: 124 Days and 11.3 Hours

A tremendous amount of data from research was published over the past decades concerning the roles of different vitamins in various gastrointestinal diseases. For instance, most vitamins showed an inverse relationship with the risk of colorectal carcinoma as well as other malignancies like gastric and esophageal cancer in observational trials, however interventional trials failed to prove a clear beneficial preventive role. On the other hand, more solid evidence was obtained from high quality studies for a role of certain vitamins in specific entities. Examples for this include the therapeutic role of vitamin E in patients with non-alcoholic steatohepatitis, the additive role of vitamins B12 and D to the standard therapy of chronic hepatitis C virus, the role of vitamin C in reducing the risk of gallstones, the positive outcome with vitamin B12 in patients with aphthous stomatitis, and the beneficial effect of vitamin D and B1 in patients with inflammatory bowel disease. Other potential uses are yet to be elaborated, like those on celiac disease, pancreatic cancer, pancreatitis, cholestasis and other potential fields. Data from several ongoing interventional trials are expected to add to the current knowledge over the coming few years. Given that vitamin supplementation is psychologically accepted by patients as a natural compound with relative safety and low cost, their use should be encouraged in the fields where positive data are available.

Keywords: Antioxidants, Colon cancer, Steatohepatitis, Alternative medicine, Supplements

Core tip: This extensive review provides a unique approach to the topic of vitamins and their use in gastrointestinal diseases. A lot of manuscripts exist about the subject, but an article specific to the practice of gastroenterology that summarises the use and benefits of vitamins is absent. While tremendous amounts of money (estimated to 13.1 billion USD in 2012) are being spent on these products, selecting the appropriate uses of these supplements remains an important issue to avoid unnecessary health expenditures.