Gluten-free communion bread will not be allowed in the Catholic Church, according to a new directive issued by the Vatican.

The Vatican said the wafers used to celebrate the Eucharist during mass must contain gluten, a protein found in wheat, even if it’s only a small amount.

“Hosts that are completely gluten-free are invalid matter for the celebration of the Eucharist,” Cardinal Robert Sarah said in a letter to bishops last month and made public on Saturday.

Bread and wafers used in the celebration of the Eucharist “must be unleavened, purely of wheat, and recently made so that there is no danger of decomposition,” Sarah said in the letter.



Cardinal Robert Sarah of Guinea receives the red biretta, a four-cornered red hat, from Pope Benedict XVI during the Consistory ceremony in Saint Peter's Basilica at the Vatican November 20, 2010. (REUTERS/Tony Gentile)

Recently, the bread has been made available for purchase in supermarkets, and even online. Sarah warned that buying the gluten-free kind would make it invalid.

Some religious leaders began offering gluten-free wafers because a growing number of congregants had celiac disease or gluten intolerance.

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