The Roman Catholic Church has taken a stand against the usage of gluten-free bread for the Sacrament of Holy Communion.
In a recent letter to bishops at the request of Pope Francis posted to the Vatican's website on Saturday, Cardinal Robert Sarah stated that gluten-free bread was an "invalid" choice for the sacrament.
The cardinal quoted from previously implemented instructions on the quality of the bread and wine used for the Communion sacrament.
"Hosts that are completely gluten-free are invalid matter for the celebration of the Eucharist," stated the letter to the bishops.
"Low-gluten hosts (partially gluten-free) are valid matter, provided they contain a sufficient amount of gluten to obtain the confection of bread without the addition of foreign materials and without the use of procedures that would alter the nature of bread."
The letter, which was sent out last month, also stressed the importance of maintaining the "worthiness of the material" used for Communion.
"In order to remove any doubt about the validity of the matter for the Eucharist, this Dicastery suggests that Ordinaries should give guidance in this regard by, for example, guaranteeing the Eucharistic matter through special certification," continued the letter.
"It is also for the Ordinary to provide information to the producers of the bread and wine for the Eucharist and to remind them of the absolute respect that is due to the norms."
In recent years, some churches have looked into offering gluten-free Communion bread for members who either suffer from Celiac disease or who are otherwise pursuing a specialized diet.
For example, the United Methodist Church released a document in 2003, titled "This Holy Mystery," which encouraged providing gluten-free bread for those with certain health needs.
"In congregations where there are people with gluten allergies, gluten-free bread may be offered. The loaf broken at the table is to be the bread distributed to the people," noted the UMC document.
The publication Harvard Health noted in an online piece that people who go on a gluten-free diet are at risk for "some nutritional deficiencies."
"Fortified breads and cereals have become a major source of B vitamins in the United States. Although breads made with white rice, tapioca, and other gluten-free flours are becoming more common, they are generally not fortified with vitamins," noted Harvard Health.
"This can be a problem for anyone, but it's especially worrisome for women who are pregnant or may become pregnant. They need vitamin B9, more commonly known as folate or folic acid, to prevent birth defects. Taking a gluten-free multivitamin-multimineral supplement is a good idea for anyone trying to avoid gluten."