Dietary gluten restriction unlikely to prevent digestive system cancers

Gluten intake does not necessarily contribute to the digestive system cancer burden among adults without coeliac disease, according to a study.

The study used data from three prospective cohorts, namely the Nurses’ Health Study (1984–2018; 73,166 women, mean age 65.1 years), Nurses’ Health Study II (1991–2017; 90,423 women, mean age 49.1 years), and Health Professionals Follow-Up Study (1986–2016; 42,617 men, mean age 64.8 years). All participants completed food frequency questionnaires.

In total, 6,231 incident digestive system cancer cases were recorded over 4,801,513 person-years of follow-up across the three cohorts.

Multivariable Cox proportional hazards regression analysis showed no association between gluten intake and the risk of digestive system cancer. The corresponding hazard ratio associated with the highest vs the lowest quintile of gluten intake was 0.94 (95 percent confidence interval, 0.87–1.02; p-trend=0.05).

On further analysis, gluten intake consistently had null associations with individual digestive system cancers, such as oral cavity and oropharyngeal cancer, oesophageal cancer, stomach cancer, small intestine cancer, colorectal cancer, pancreatic cancer, gallbladder cancer, and liver cancer.

Gluten is known to trigger an immune reaction that damages small intestinal villi in patients with coeliac disease, and this potentially increases the long-term risk of gastrointestinal cancer. However, for individuals without coeliac disease, the present data indicate that gluten has no meaningful health impact. Therefore, restricting dietary gluten may not really be beneficial in the prevention of digestive system cancers in the general population.