The Nutritional Content of Holy Communion

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​It's the time of the year when people examine their eating habits. Every morsel that goes into one's mouth is scrutinized for its caloric content in hopes that reducing food intake a little bit will result in the body of your dreams. The one thing many people forget, however, is the caloric content of Holy Communion.

You might think that the bread and wine you take each Sunday is guilt-free and calorie-free, but can you be sure?

Communion wafers, called Hosts by Catholics, are essentially matzoh: a paste of water and wheat flour mixed together and baked before it has a chance to rise. It's not unreasonable to use matzoh as a guide: 110 calories per ounce of matzoh is probably close to 110 calories per ounce of Hosts. (Bonus facts: Hosts are available in white or wheat, as well as gluten-free for those with celiac disease.)

Patnac @ wikimedia.org

​Amazon and other sites quote the shipping weight of 1,000 average-size Hosts at 8.8 ounces. Allowing the decimal to drop off to cover the weight of the box, this gives us 8 ounces per 1,000 Hosts, or 125 Hosts per ounce. At 110 calories per ounce, this works out to 0.88 calories per Host.

Sacramental wine may taste terrible, but it isn't substantially different, nutritionally speaking, than any other wine. In point of fact, at the time of the vendange in the wine-growing regions of France, it is not uncommon for the church to receive locally-produced wine for use in Masses. Unfortified wines range from about 90 to 130 calories per 5-fluid-ounce serving. Sacramental wine tends toward the sweeter end of the spectrum, so let's be conservative and say 120 calories per 5 oz., or 24 calories per ounce. Each half-ounce sip of wine (we'll cover that later) gives you 12 calories' worth of wine. Add this to your bread and you've consumed nearly 13 calories in the ten seconds it takes you to move across the front of the church.

Roman Catholics believe in transubstantiation--that is, the bread and wine during the Eucharistic celebration at Mass are actually turned into the real Body and Blood of Jesus Christ before they enter the communicant's mouth. This is why there are so many rules around what you can and cannot do with Eucharistic vessels, why the tabernacle (where unused consecrated Hosts are stored) is the most important part of any Catholic church, and why a silver salver is held under the mouths of fresh-faced second-graders when they take their First Holy Communion: to catch any crumbs.

This gives rise to an important question: how long would it take a faithful Catholic to consume Jesus Christ entirely--or failing that, since there is clearly some miraculous extension of His Body and Blood to cover the millions and millions of faithful, how long would it take to consume an equivalent mass of transubstantiated Eucharist?