It clearly refers the Eucharist.
The word used for eat does not mean consume it means “ gnaw” as of flesh. It is because he referred to eating his flesh and drinking his blood that the Jews were horrified. Many of his supporters left in disgust. Jesus did not call them back.
Paul says that “ some are sick, some have died” because of profaning it. So it is no mere symbol.
Thats why johns disciples talk clearly of a eucharist of the real flesh, valid only if presided by bishop in succession, it is also why the Romans misunderstood what they were told by tortured deacons, they considered Christians were cannibals.
Fast forward to the generation of the creed and New Testament canon where anasthasius of council of nicea says clearly “ before the blessing is just bread and wine, after it is the body and blood of our Lord.
That is what all Christians believed unchanged till the reformation.
Jesus says unless you eat of it, you have no life in you. If you do he will raise you up.
It is not a symbol.
And as the forensics of many Eucharistic miracles confirm - it can sometimes be seen as living heart myocardium, with the trauma of beating.