(Parishioners pray at Immaculate Conception Catholic Church in Chicago April 10, 2008. Once solidly Irish, Italian and Polish, U.S. Catholicism is turning Hispanic and even a bit Vietnamese and African -- and immigration is keeping the church from losing its "market share" in the highly competitive field of faith in America.Picture taken April 10, 2008. REUTERS/John Gress )

(Parishioners pray at Immaculate Conception Catholic Church in Chicago April 10, 2008. REUTERS/John Gress )

A growing number of U.S. Hispanics are turning away from the Roman Catholic religion of their youth and now identify as Protestant or unaffiliated with any church, according to a survey released on Wednesday.

Catholics represented 55 percent of U.S. Hispanics in 2013, a drop from 67 percent in 2010, the Pew Research Center survey found. About 16 percent of Hispanics are evangelical Protestants, up from 12 percent three years earlier, and 18 percent are unaffiliated, up from 10 percent.

Three-quarters of those interviewed said they were raised Catholic. More than half of those who left their childhood faith said they “gradually drifted away,” while 31 percent said they found a congregation that helps its members more.

Religious scholars said the shift could serve as something of a warning to U.S. Catholic leaders, who have relied on the growing Hispanic population to fill pews and collection plates.