In Jewish communities across the globe, stores are stocking shelves with Kosher for Passover (KFP) products. And people with celiac disease, or their parents, whether Jewish or not, are stocking up on KFP foods for their children. What’s the connection?

The central food of the week-long Jewish holiday of Passover is matzah. Matzah can be made of any of five species: barley, oats, rye, spelt and wheat. Wheat is the only kind generally available. Because of the quantities required and the strict rules surrounding its production, matzah is generally made in a separate factory.

Eating matzah is an important part of the Seder, the festive meal served on the first night of Passover. This doesn’t concern non-Jews with celiac. What’s important for celiac sufferers is the prohibition against leavened foods, or chametz.