Eucharistic miracles are reported events in which the consecrated host or wine in the Catholic Eucharist is said to visibly transform, often into human heart tissue or blood. These occurrences are believed by the Catholic Church to be rare signs meant to strengthen belief in the doctrine of the Real Presence of Jesus Christ in the Eucharist. One of the most well-known cases is the Miracle of Lanciano in Italy, where bread is said to have become real human heart tissue. Many of these miracles have been investigated over centuries. They continue to be a subject of devotion, scientific curiosity, and theological reflection within the Church.