Turns out that germophobes may be right about the whole “blowing out the candles” thing.
A recent study in the Journal of Food Research found that blowing out the candles produces 1,400 percent more bacteria in cake icing than in icing not blown on.
The report, titled “Bacterial Transfer Associated with Blowing Out Candles on a Birthday Cake,” found that more than 2,000 “moisture particles” are exhaled when blowing out candles, each particle large enough to carry bacteria and viruses. Some of the bacteria identified in the study include staphylococcus, corynebacterium, haemophilus and neisseria.
Instead of baking real cakes, researchers at Clemson University spread cake frosting on Styrofoam wrapped in aluminum foil, then blew out the candles on some and not on others, to compare bacterial counts. Before blowing out the candles, researchers ate pizza to get into a party mood.
“We also wanted to simulate a birthday party,” study co-author Paul Dawson told The Atlantic. “We thought it might help the salivary glands get going.”
Dawson also told The Atlantic that he’s not too bothered by the findings.
“It’s not a big health concern, in my perspective,” he said. “In reality, if you did this 100,000 times, then the chance of getting sick would probably be very minimal.”