For non-Catholics, the quick answer is
For Roman Catholics, who believe in transubstantiation, the answer is also
no, but understanding why requires some explanation.
Communion is based on Luke 22:19-20 and other gospel accounts of Jesus's last meal:
And he took bread, and gave thanks, and brake it, and gave unto them, saying,This is my body which is given for you: this do in remembrance of me.Likewise also the cup after supper, saying,This cup is the new testament in my blood, which is shed for you.
Most Christian denominations have a ceremony in which small amounts of bread and wine are consumed. Some perform this only once a year, on the anniversary of that final meal; many celebrate the event at weekly services; and others, Roman Catholics in particular, offer communion more frequently.
For most denominations, the bread and wine are purely symbolic, serving as a reminder of what Jesus sacrificed, having no special power, and being no different from ordinary bread and wine.
Lutherans believe in consubstantiation, in which Jesus becomes present within the bread and wine. The bread does become special, yet it reamins bread.
But Catholics, who regard communion as one of their basic sacraments,
is my body to be literally true.
During the communion sacrament, the bread and wine take on special powers and actually become Jesus's body and blood.
But understanding what that really means, again requires some explanation.
When describing things using formal logic, the term
essence refers to attributes that are fundamental to the object, while
accident refers to attributes that aren't.
A table could be made of wood, of metal, of plastic, or of some other substance. Which material is used is considered accident, not essence. Which specific material that tables are made of has nothing to do with the state of being a table.
Similarly, a wooden table and the inside of a tree are composed of the same substance, but one would not consider the table to be a tree. Being made of wood is essence when it comes to defining a tree, but accident when defining a table.
The same situation applies to bread (and wine). During the communion sacrament, the bread turns into Jesus's body just as a piece of wood can be turned into a table.
In the same way that the table is no longer a piece of wood, so too, the sacrifice is no longer a piece of bread. The table may be physically composed of the same thing that trees are composed of, but it is not a tree; wood is an essence of tree, but accident of table. A sample taken from the table would be indistinguishable from a sample taken from a tree, but that doesn't mean that the table is a tree. Similarly, this aspect of the body of Christ may be physically composed of flour, but it is no longer bread; flour is an essence of bread, but accident of Christ's body.
A piece of wood starts as essence with respect to tree and becomes accident with respect to table. The wood itself is there, but it has nothing to do with the table's essence.
Gluten starts as essence with respect to wheat bread and becomes accident with respect to the body of Christ. The flour itself is there, but it has nothing to do with the body of Christ's essence.
A table might sometimes be made of wood, but its essence is table, not wood. The body of Christ might sometimes be made of flour, but its essence is Christ, not flour.
The bread transforms into the body of Christ, but that does not mean that flour turns into meat any more than transforming a tree into a table turns it into metal or plastic.
So just to be sure: transubstantiation does not make communion safe for people with celiac disease or wheat allergies.