Eucharist

===Health issues===
====Gluten====
{{Main|Coeliac disease#Christian churches and the Eucharist}}
The [[gluten]] in wheat bread is dangerous to people with [[celiac disease]] and other [[gluten-related disorders]], such as [[non-celiac gluten sensitivity]] and [[wheat allergy]].<ref name=MulderWanrooijQuotation>{{cite journal |vauthors=Mulder CJ, van Wanrooij RL, Bakker SF, Wierdsma N, Bouma G |title=Gluten-free diet in gluten-related disorders |journal=Dig. Dis. |volume=31|issue=1|pages=57–62|date=2013|pmid=23797124|doi=10.1159/000347180 |s2cid=14124370 |type= Review |quote= The only treatment for [[coeliac disease|CD]], [[dermatitis herpetiformis]] (DH) and [[gluten ataxia]] is lifelong adherence to a [[gluten-free diet|GFD]].}}</ref><ref name=HischenhuberCrevelQuotation>{{cite journal |vauthors=Hischenhuber C, Crevel R, Jarry B, Mäki M, Moneret-Vautrin DA, Romano A, Troncone R, Ward R|title=Review article: safe amounts of gluten for patients with wheat allergy or coeliac disease |journal=Aliment Pharmacol Ther |volume=23|issue=5|pages=559–75|date=1 March 2006|pmid =16480395|doi=10.1111/j.1365-2036.2006.02768.x |s2cid=9970042 |quote=For both [[wheat allergy]] and coeliac disease the dietary avoidance of wheat and other gluten-containing cereals is the only effective treatment.|doi-access=free}}</ref><ref name=VoltaCaio2015Quotation>{{cite journal |vauthors=Volta U, Caio G, De Giorgio R, Henriksen C, Skodje G, Lundin KE|title=Non-celiac gluten sensitivity: a work-in-progress entity in the spectrum of wheat-related disorders |journal=Best Pract Res Clin Gastroenterol |volume=29|issue=3|pages=477–91|date=Jun 2015 |pmid=26060112 |doi=10.1016/j.bpg.2015.04.006 |quote=A recently proposed approach to [[non-celiac gluten sensitivity|NCGS]] diagnosis is an objective improvement of gastrointestinal symptoms and extra-intestinal manifestations assessed through a rating scale before and after [[gluten-free diet|GFD]]. Although a standardized symptom rating scale is not yet applied worldwide, a recent study indicated that a decrease of the global symptom score higher than 50% after GFD can be regarded as confirmatory of NCGS (Table 1) [53]. […] After the confirmation of NCGS diagnosis, according to the previously mentioned work-up, patients are advized to start with a GFD [49].}}</ref> For the Catholic Church, this issue was addressed in the 24 July 2003 letter<ref>[http://www.adoremus.org/CDF_Lowgluten-mustum2003.html letter] {{Webarchive|url=https://web.archive.org/web/20101229140229/http://www.adoremus.org/CDF_Lowgluten-mustum2003.html |date=29 December 2010 }}</ref> of the [[Congregation for the Doctrine of the Faith]], which summarized and clarified earlier declarations. The Catholic Church believes that the matter for the Eucharist must be wheaten bread and fermented wine from grapes: it holds that, if the gluten has been entirely removed, the result is not true wheaten bread.<ref>{{cite web |url=http://www.ewtn.com/library/Liturgy/zlitur47.htm |title=Gluten-free Hosts |access-date=2008-04-22 |last=McNamara |first=Father Edward |date=2004-09-14 |work=ZENIT International News Agency |archive-date=4 May 2008 |archive-url=https://web.archive.org/web/20080504055320/http://www.ewtn.com/library/Liturgy/zlitur47.htm |url-status=dead }}</ref> For celiacs, but not generally, it allows low-gluten bread. It also permits Holy Communion to be received under the form of either bread or wine alone, except by a priest who is celebrating Mass without other priests or as principal celebrant.<ref>The same 24 July 2003 letter of the [[Congregation for the Doctrine of the Faith]].</ref> Many Protestant churches offer communicants gluten-free alternatives to wheaten bread, usually in the form of a rice-based or other gluten-free wafer.<ref>Jax Peter Lowell, [https://books.google.com/books?id=IRhm1A2_EkkC ''The Gluten-Free Bible''], p. 279.</ref>

===={{anchor|Alcohol}}Alcohol====
{{See also|Christian views on alcohol}}
The Catholic Church believes that grape juice that has not begun even minimally to ferment cannot be accepted as wine, which it sees as essential for celebration of the Eucharist. For non-alcoholics, but not generally, it allows the use of [[mustum]] (grape juice in which fermentation has begun but has been suspended without altering the nature of the juice), and it holds that "since Christ is sacramentally present under each of the species, communion under the species of bread alone makes it possible to receive all the fruit of Eucharistic grace. For pastoral reasons, this manner of receiving communion has been legitimately established as the most common form in the Latin rite."<ref>{{Cite web|url=https://www.vatican.va/archive/ENG0015/__P42.HTM|archiveurl=https://web.archive.org/web/20120616060732/https://www.vatican.va/archive/ENG0015/__P42.HTM|url-status=dead|title=Catechism of the Catholic Church – IntraText|archivedate=16 June 2012|website=www.vatican.va}}</ref>

As already indicated, the one exception is in the case of a priest celebrating Mass without other priests or as principal celebrant. The water that in the [[Roman Rite]] is prescribed to be mixed with the wine must be only a relatively small quantity.<ref>{{Cite web|url=https://www.vatican.va/archive/ENG1104/__P3A.HTM|archiveurl=https://web.archive.org/web/20101204185953/https://www.vatican.va/archive/ENG1104/__P3A.HTM|url-status=dead|title=Code of Canon Law, canon 924 §1|archivedate=4 December 2010}}</ref> The practice of the [[Coptic Church]] is that the mixture should be two parts wine to one part water.<ref>{{cite web|url=http://www.copticchurch.net/topics/thecopticchurch/sacraments/4_eucharist.html |title=Sacrament of the Eucharist: Rite of Sanctification of the Chalice |publisher=Copticchurch.net |access-date=2019-05-16}}</ref>

Some Protestant churches allow communion in a non-alcoholic form, either normatively or as a pastoral exception. Since the invention of the necessary technology, grape juice which has been [[pasteurization|pasteurized]] to stop the fermentation process the juice naturally undergoes and de-alcoholized wine from which most of the alcohol has been removed (between 0.5% and 2% remains) are commonly used, and more rarely water may be offered.<ref>Compare John Howard Spahr, [http://www.religion-online.org/showarticle.asp?title=1605 I Smell the Cup] {{webarchive|url=https://web.archive.org/web/20080921224625/http://www.religion-online.org/showarticle.asp?title=1605 |date=21 September 2008 }}, ''Christian Century'', 12 March 1974, pp. 257–59.</ref> Exclusive use of unfermented grape juice is common in [[Baptist]] churches, the [[United Methodist Church]], [[Seventh-day Adventists]], [[Christian Churches/Churches of Christ]], [[Churches of Christ]], [[Church of God (Anderson, Indiana)]], some [[Lutheranism|Lutherans]], [[Assemblies of God]], [[Pentecostals]], [[Evangelicals]], the [[Christian Missionary Alliance]], and other American [[Nondenominational Christianity|independent]] Protestant churches.

====Transmission of diseases====
{{See also|Impact of the 2019–20 coronavirus pandemic on religion}}
Risk of infectious disease transmission related to use of a common communion cup exists but it is low. No case of transmission of an infectious disease related to a common communion cup has ever been documented. Experimental studies have demonstrated that infectious diseases can be transmitted. The most likely diseases to be transmitted would be common viral illnesses such as the [[common cold]]. A study of 681 individuals found that taking communion up to daily from a common cup did not increase the risk of infection beyond that of those who did not attend services at all.<ref>{{cite journal |title=Risk of Infectious Disease Transmission from a Common Communion Cup |first1=Lilia P. |last1=Manangan |first2=Lynne M. |last2=Sehulster |first3=Linda |last3=Chiarello |first4=Dawn N. |last4=Simonds |first5=William R. |last5=Jarvis |journal=American Journal of Infection Control |date=October 1998 |volume=26 |issue=5 |pages=538–39 |url=http://www.ntnl.org/index.php/component/docman/doc_download/470-common-cup-cdc |doi=10.1016/s0196-6553(98)70029-x |pmid=9795685 |access-date=2 December 2013 |archive-url=https://web.archive.org/web/20131203012335/http://www.ntnl.org/index.php/component/docman/doc_download/470-common-cup-cdc |archive-date=3 December 2013 |url-status=dead }}</ref><ref>{{Cite journal | last1 = Pellerin | first1 = J. | last2 = Edmond | first2 = M. B. | doi = 10.1016/j.ijid.2013.05.001 | title = Infections associated with religious rituals | journal = International Journal of Infectious Diseases | volume = 17 | issue = 11 | pages = e945–48 | year = 2013 | pmid =  23791225| doi-access = free }}</ref>

In influenza epidemics, some churches suspend the giving wine at communion, for fear of spreading the disease. This is in full accord with Catholic Church belief that communion under the form of bread alone makes it possible to receive all the fruit of Eucharistic grace. However, the same measure has also been taken by churches that normally insist on the importance of receiving communion under both forms. This was done in 2009 by the [[Church of England]].<ref>{{cite web|url=http://www.christiantoday.com/article/archbishops.advise.against.sharing.chalice.during.swine.flu.pandemic/23882.htm |title=Archbishops advise against sharing chalice during swine flu pandemic |publisher=Christiantoday.com |date=2009-07-27 |access-date=2019-05-16}}</ref>

Some fear contagion through the handling involved in distributing the hosts to the communicants, even if they are placed on the hand rather than on the tongue. Accordingly, some churches use mechanical wafer dispensers or "pillow packs" (communion wafers with wine inside them). While these methods of distributing communion are not generally accepted in Catholic parishes, one parish provides a mechanical dispenser to allow those intending to commune to place in a bowl, without touching them by hand, the hosts for use in the celebration.<ref>{{cite news| first= Sumathi |last=Reddy |url= https://www.wsj.com/articles/SB10001424052748704415104576065982762908782 |title= Hands Off After Wafer Scare| newspaper= Wall Street Journal| date=7 January 2011| access-date=2012-10-12}}</ref>