At Holy Communion, Christians are encouraged to eat the body of Christ and drink his blood. I've never done it myself, but it doesn't sound very nice.
This stems from the metaphor Jesus spoke during the Last Supper.
Only the Catholics say that the bread and wine are magically transformed into the actual body and blood of Christ. During the Last Supper, "While they were eating, Jesus took bread, and when he had given thanks, he broke it and gave it to his disciples, saying, “Take and eat; this is my body.” Then he took a cup, and when he had given thanks, he gave it to them, saying, “Drink from it, all of you. This is my blood of the new covenant, which is poured out for many for the forgiveness of sins." (Matthew 26:26-28) This is metaphor. It was bread and wine, not actual flesh and blood. It is entirely celebratory of the new covenant.
"Many denominations partake of the Communion, or Holy Eucharist. Churches in which worship is a more formal, liturgical style are very likely to celebrate Communion every week. These include the Roman Catholic Church, the Episcopal Church USA, the Orthodox Church in America, the Antiochan Orthodox Christian Diocese of North America, the Serbian Orthodox Church of the USA and Canada, the Greek Orthodox Archdiocese of North America, and the Ukrainian Orthodox Church of the USA.
"Denominations with a less liturgical structure often do not celebrate Communion weekly. However, some that do are the Christian Church (Disciples of Christ), the Christian Church and Churches of Christ, the Church of Christ and the Plymouth Brethren.
"There are a number of denominations in which individual congregations are allowed to decide for themselves how often to celebrate Communion. The United Methodist Church states that "communion may be celebrated as often as desired." The Christian reformed Church in North America allows freedom, but requires Communion to be celebrated at least four times per year. The International Pentecostal Holiness Church requires it at least once per year. Many other independent churches, not affiliated with a particular denomination, may choose to celebrate Communion weekly."