The Vatican has issued guidelines over the type of bread and wafers to use during communion in Catholic churches at the request of the pope, since these items are widely for sale, including online. (Domenico Stinellis/AP)

A new Vatican letter to Catholic bishops worldwide has stirred up questions again over what kinds of bread and wafers should be used during communion in Catholic churches around the world. The letter sparked concerns for those who avoid eating gluten, including people who have celiac disease.

The letter drew attention from media outlets around the globe, but it actually reaffirmed earlier guidelines saying that bread and wafers must have at least some gluten in them. The U.S. Conference of Catholic Bishops already has guidelines allowing churches to use low-gluten wafers and nothing will change in American Catholic churches, said Andrew Menke, executive director of the Secretariat of Divine Worship.

“Absolutely nothing has changed,” Menke said in a statement. “The ‘new guidance’ from the Vatican is simply a reminder to bishops that they need to be attentive to the bread and wine that is used for Mass, making sure that it’s consistent with the Church’s requirements.”

The guidelines were issued in June but began to cause a stir after they were published Saturday by Vatican Radio. They were issued at the request of Pope Francis, according to Cardinal Robert Sarah, since bread and wine are widely available for sale, “even over the Internet.”

The Catholic Church holds communion, also called the Eucharist, at every mass as a recognition of Jesus’ Last Supper. Catholics receive bread and wine, believing that they are receiving the literal body and blood of Christ.

People with celiac disease, an autoimmune disorder where gluten can lead to damage in the small intestine, avoid foods with the protein found in grains like wheat, rye and barley. But researchers say gluten-free diets have been on the rise in the United States even among those who don’t have a gluten sensitivity, and many Protestant churches across the country have begun to offer gluten-free communion in recent years.

Because the Catholic Church is global, it has long wrestled with how to remain unified while accommodating churches in different regions in the world to adapt its practices to cultural norms. Some Catholics have discussed whether the church should consider whether the bread could be made of something else, like rice, or whether the wine could be made from the sap of palm trees.

The Catholic Church teaches that the practice of the Eucharist should be in continuity with Jesus, who ate wheat bread and drank grape wine, describing them as his body and blood.

“Christ did not institute the Eucharist as rice and sake, or sweet potatoes and stout,” said Chad Pecknold, a theology professor at Catholic University.

Some theologians have argued the bread and wine are simply symbolic, but the Catholic Church does not consider the elements to be symbols. It teaches that Jesus himself instituted the bread and the wine during the Passover meal, and churches should follow his lead.

“It may seem a small thing to people,” Pecknold said. “But the Catholic Church has spent 2,000 years working out how to be faithful to Christ even in the smallest things. To be vitally and vigorously faithful … is something which is simply integral to what it means to be Catholic.”

Bread and wafers “must be unleavened, purely of wheat, and recently made so that there is no danger of decomposition,” the letter from the Vatican states. “Hosts that are completely gluten-free are invalid matter for the celebration of the Eucharist.” However, low-gluten wafers and bread may be used, it says.

The wine, the letter says, must be “natural, from the fruit of the grape, pure and incorrupt, not mixed with other substances.” Both bread and wine made from genetically-modified organisms are acceptable.

Rachel Rieger, who was diagnosed with celiac disease at 12 years old, said she was worried whether the guidelines would change something for her. She said even one wafer would make her feel sick for the next 24 to 48 hours, and her parish in Ohio began to provide her with low-gluten wafers.

Rieger, a 25-year-who works in digital marketing, said the guidelines seem so specific for a global church that should be universal.

“It’s almost splitting hairs,” she said, wondering why the church won’t allow nonwheat wafers. “There are so many options, and it would reach that same end point.”

Marie Jona Yoo of Benedictine Sister of Perpetual Adoration pours batter on a hot plate used to bake low-gluten altar breads. The Benedictine Sisters are the largest religious producers of altar breads in the United States. (Kelley Baldwin)

The Benedictine Sisters of Perpetual Adoration in Clyde, Mo., became the first community to produce low-gluten altar breads that were approved by the U.S. bishops in 2003. A spokeswoman said they sell 15,000 low-gluten breads each week and declined to share sales figures.

In 2004, Alessio Fasano, who was then director of the Center for Celiac Research at the University of Maryland, said that one of the Benedictine Sisters’ low-gluten wafers contained such low gluten that someone with celiac disease would have to consume 270 wafers daily to reach a danger point.

“You’d have to be very devout or really excited about going to church to eat that much at communion,” said Claire Baker, spokeswoman for Beyond Celiac, an advocacy organization for people with celiac disease. “You don’t eat communion wafers like you eat crackers.”

A regular wafer contains approximately 22 milligrams of gluten, according to registered dietitian Nancy Patin Falini. Wafers that contain under 10 milligrams of gluten are considered low-gluten.

The Vatican letter also reaffirmed the existing practice of using mustum, a grape juice where fermentation has begun before the alcohol content (usually less than 1 percent) reaches the levels found in most table wines. The letter recommends the grape juice as a substitute for communion wine for worshipers who could not tolerate alcohol.

People with an alcohol intolerance and people with a gluten intolerance have very different reactions to the wine or food.

“With alcoholism, many don’t even have a drop of alcohol as it could spiral them out of control,” Baker said. “A little bit of gluten doesn’t want to make me want to eat a cake. It’s almost the opposite.”

Clarification: This story has been updated to clarify the title of Alessio Fasano, who in 2004 was the director of the Center for Celiac Research at the University of Maryland. He is now director of the Center for Celiac Research and Treatment at Massachusetts General Hospital in Boston.