Published online Jun 28, 2019. doi: 10.3748/wjg.v25.i24.2973
Peer-review started: January 16, 2019
First decision: March 27, 2019
Revised: April 15, 2019
Accepted: April 29, 2019
Article in press: April 29, 2019
Published online: June 28, 2019
Until recently, with the exception of coeliac disease, gastroenterologists have not been particularly interested in the role of diet in the management of gastrointestinal disorders. However, patients have always felt that diet must play a part in their symptoms and, in the absence of any medical interest, have turned to alternative dietary practitioners for help, which can often have no evidence base. Fortunately, with the advent of the FODMAP diet (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) and the realisation that diet can have a profound effect on the microbiome, medical opinion is now changing. Nevertheless, research on the various diets that are now available is often completely lacking. Lectins are carbohydrate binding proteins which are widely distributed in nature and are found in a whole variety of commonly consumed foods. It seems likely that the exclusion of lectins from the diet could become the next “food fashion” for alternative practitioners to promote, especially as there is some evidence to suggest that certain lectins may be harmful to health. It is, therefore, the purpose of this viewpoint to try and stimulate research on the dietary effects of lectins, which is currently minimal, so that we can pre-empt a situation where we are unable to give patients or the public evidence based advice on this topic.
Core tip: Patients with gastrointestinal problems, as well as the general public, are being offered an increasing number of different diets which claim to improve their health, often without any evidence to support a beneficial effect. Lectins are carbohydrate binding proteins which are found in many foods and some of them, such as those found in red kidney beans, can cause gastrointestinal symptoms if not cooked properly. Consequently, it is possible that a lectin exclusion diet could become fashionable in the future and research is needed to find out under what circumstances, if any, such a diet may be advisable.