Ick! Here’s How Much Blowing Out Birthday Candles Ups Cake Bacteria

Read at your own risk, germaphobes.

A birthday cake is no different from an everyday cake if it doesn’t involve some candle-blowing and wish-making fun. But have you ever thought about how birthday cakes literally get sprayed with a mouthful of germs before we eat them? Well, now you have.

The folks over at the Atlantic chatted with Paul Dawson, lead author of a new study, titled “Bacterial Transfer Associated with Blowing Out Candles on a Birthday Cake”, to find out just how many more germs end up landing on the average birthday cake than if we were to skip the whole blowing-all-over it part. (And, you know, to ruin all birthdays to come. Kidding.) The answer: A lot more.  

Dawson, a professor of food safety at Clemson University, and his associates created a mock cake — candles and all — to test how germ-y cakes can be. After lighting and blowing out the candles, the group tested the frosting of the cake to count bacteria. On average, blowing out the candles on a cake increased the amount of bacteria on the frosting by — wait for it — 1400 percent. Ick!

But really, this isn’t a huge deal. “In reality if you did this 100,000 times, then the chance of getting sick would probably be very minimal,” Dawson told the Atlantic. Our mouths are full of bacteria, but not much of it is harmful. If it were, we would all probably have fewer embarrassing bar make-out stories, right? But, if nothing else, this news may help you from blowing your diet on every birthday cake that makes its way through your office kitchen. (How is it ALWAYS someone’s birthday?)

Like what you’re reading? Stay in touch with Be Well Philly—here’s how: