As one examines packages nowadays in the grocery stores and supermarkets, it is apparent that, like being kosher or halal or sugar-free or vegan, many foodstuffs are marked as being gluten-free. During Pesach, there was even kosher l’Pesach gluten-free matzah, which seems amazing, though I refer you to Rabbi Jachter or one of the other columns in The Link as to whether one can use it for the Seder. I have no doubt that many consumers take this as some sort of important health indicator and preferentially purchase products that are gluten-free, presuming that they are thereby protecting their own and their family’s health. But is this true? Is there any reason to avoid gluten, either from a cancer point of view or any other point of view?
I have been a member of the Celiac Disease Center at Columbia, one of the leading such centers in the U.S., which helps the clinical needs of people with this disease that involves problems related to gluten exposure. As a member and friend of the Center, I have occasionally attended their fundraising dinners, which serve gluten-free meals (kosher on request), and let me tell you that it is no pleasure to be gluten-free, especially when it comes to gluten-free beer.
What is gluten? It is a protein found in wheat, but this encompasses various species, such as barley, rye and spelt. Gluten is generally harmless in and of itself, but some people may develop a sensitivity to it. Celiac disease is basically an immune response to gluten, and is present in about 1% of the white population of the U.S. and West, with lower rates in those of African descent. Those who have celiac disease have a spectrum of symptoms and manifestations that include GI symptoms and increased risk of certain cancers (small bowel cancer and lymphoma) and other diseases as well, but I will not dwell on celiac disease here. The disease is best diagnosed with a biopsy of the small intestine, though there are now serum antibody tests that are quite accurate also. Treatment requires strict gluten avoidance and with that, the disease can be well controlled. There also seems to be a very small fraction of the population who have gluten sensitivity that is non-celiac but for whom gluten avoidance can also relieve the symptoms (so-called non-celiac gluten or wheat sensitivity).
But what about the remaining 98% of the population? Is there any benefit from avoiding gluten? In truth, there is a dearth of studies showing any cause for alarm. In particular, I refer to the work of Benjamin Lebwohl, a former fellow of mine at Columbia, who is now the director of research at the Celiac Center at Columbia and a noted expert in the clinical management and epidemiology of celiac disease. He is a graduate of Ramaz, Harvard College and Columbia’s College of Physicians and Surgeons. Ben has published several studies in collaboration with investigators at Harvard that investigate the impact of gluten exposure on presumably healthy individuals with regard to several key chronic diseases.
As we have mentioned in prior articles, investigators at the Harvard School of Public Health maintain several long-term cohorts for study, including the Nurses Health Study and the Health Professional Follow-Up Study, which together encompass over 100,000 men and women followed for over 20 years on whom excellent dietary information has been ascertained at or shortly after recruitment into the study. Thus, Ben and his collaborators were able to estimate on these individuals their consumption of gluten and to follow them prospectively for the incidence of various conditions.
In 2017, they published their initial findings in the British Medical Journal. The relative intake of gluten in healthy individuals (high versus low) was not associated with the incidence of coronary heart disease. In another paper published last year, they also determined that gluten intake was not associated with cancers of the digestive system (oropharyngeal cancer, esophageal cancer, stomach cancer, small bowel cancer, colorectal cancer, pancreatic cancer, liver cancer or biliary cancer). Yet another study showed that gluten intake was not associated with variation in cognitive function or intellectual functioning. And, importantly, it was not associated with the risk of developing inflammatory bowel disease (Crohn’s disease and ulcerative colitis).
Gluten intake was, however, inversely associated with risk of Type 2 diabetes. This may be because avoidance of gluten generally involves reducing carbohydrate intake more generally (grains, starch, cereals). Thus, as a secondary outcome, one gets a reduced incidence of Type 2 diabetes—however, this does not appear to be directly related to gluten itself.
Overall, one can conclude that gluten seems safe for those without a clear-cut sensitivity to it.
Alfred I. Neugut, MD, PhD, is a medical oncologist and cancer epidemiologist at Columbia University Irving Medical Center/New York Presbyterian and Mailman School of Public Health in New York.
This article is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment, and does not constitute medical or other professional advice. Always seek the advice of your qualified health provider with any questions you may have regarding a medical condition or treatment.
