Blowing out birthday candles on a cake is one of those traditions that we all just do without really questioning why. But, you might want to rethink eating the cake under the candles at the next birthday party you go to.
A new study from researchers at Clemson University in South Carolina found that blowing out birthday candles drastically increases the amount of bacteria on the cake.
For the study, researchers created several fake birthday cakes made of tin foil and a Styrofoam base, frosted them and added candles. Then, they compared the levels of bacteria between cakes with candles that were blown out and cakes with candles that weren’t. The results found that, unsurprisingly, there was a huge difference in the amount of bacteria found on the cake with the candles blown out.
However, the amount of bacteria depended on the force of the blow: The average blow increased bacteria to 14 times that of the other cakes; while other blows increased the bacteria by a staggering 120 times.
But don’t cancel your party just yet.
“It’s not a big health concern in my perspective,” Paul Dawson, study co-author and professor of food safety at Clemson University, told The Atlantic. We all get extra bacteria on our food from time-to-time — sometimes it’s harmless (like from double-dipping or sharing food with friends), while other times it’s dangerous (like getting sick from restaurant food).
“In reality if you did this 100,000 times, then the chance of getting sick would probably be very minimal,” he added.
At the very least, it’s probably a good idea to steer clear of the cake if the birthday boy or girl is obviously sick, or skip it altogether if the whole idea of eating bacteria grosses you out. You avoid the bacteria and the extra sugar.