Turns out, a high gluten intake by mothers during pregnancy is associated with an increased risk of their child developing type 1 diabetes.

Gluten is a general name for the proteins found in wheat, rye, and barley and is suggested to affect the development of type 1 diabetes. In animal studies, a gluten-free diet during pregnancy almost completely prevented type 1 diabetes in offspring.

To better understand the nature of this association, researchers set out to examine whether gluten intake during pregnancy is associated with subsequent risk of type 1 diabetes in children. They analyzed data for 63,529 pregnant women enrolled in the Danish National Birth Cohort between January 1996 and October 2002.

Women reported their diet using a food frequency questionnaire at week 25 of pregnancy and information on type 1 diabetes in their children was obtained through the Danish Registry of Childhood and Adolescent Diabetes. Average gluten intake was 13 gram per day, ranging from less than 7 gram per day, to more than 20 gram per day, and the researchers identified 247 cases of type 1 diabetes (a rate of 0.37%) among the participants' children.

After taking account of potentially influential factors, such as mother's age, weight (BMI), total energy intake, and smoking during pregnancy. They found that the child's risk of type 1 diabetes increased proportionally with the mother's gluten intake during pregnancy (per 10 gram per day increase).

For example, children of women with the highest gluten intake (20 gram per day or more) versus those with the lowest gluten intake (less than 7 gram per day) had double the risk of developing type 1 diabetes over a mean follow-up period of 15.6 years.

The mechanisms that might explain this association are not known but could include increased inflammation or increased gut permeability (so-called leakiness of the gut). The authors, say doctors, researchers, and the public "should be aware of the possibility that consuming large amounts of gluten might be associated with an increased risk for the child to develop type 1 diabetes, and that further studies are needed to confirm or rule out these findings, and to explore possible underlying mechanisms." The study appeared in the Journal of The BMJ.