We Spill Coffee All Over Ourselves Because We Hold Our Cups Wrong

By Noah Kaufman |

Bill Varie / Alamy

We’ve all been there—rushing to some early morning meeting about company synergy, barely able to keep our eyes open because honestly, who is awake at this godforsaken hour—and it happens: A coffee spill all over our ironic t-shirt. Admit it, you still wear ironic t-shirts. But the crux problem remains: Coffee spillage. New in depth, mathematical and physics-based research (the best kind of research) has done a deep dive into why we spill coffee all over ourselves, and, the solution to our problems could all be in the way we hold our cups.

The study, entitled The Coffee Spilling Phenomena in the Low Impulse Regime, starts with a simple premise. In the words of study author Jiwon Han, “Rarely do we manage to carry coffee around without spilling it once. In fact, due to the very commonness of the phenomenon, we tend to dismiss questioning it beyond simply exclaiming: “Jenkins! You have too much coffee in your cup!”

Now, amusing exclamations aside, what Han discovered was that there were two ways to reduce the chances of spilling when carrying coffee. One is to alter your grip. Rather than holding your mug by the handle, carry it by gripping the top—he calls this “the claw method.” The reason, says Han, is because carrying the mug by the top shrinks “the magnitude of acceleration,” that is to say, it causes us to swing our coffee around in a much gentler manner.

The other way to keep coffee in your mug according to Han is by walking backwards. Why? “Since we are not accustomed to backwards walking, our motion in the walking direction becomes irregular, and our body starts to heavily rely on sideways swinging motion in order to keep balance.”

There are some serious graphs and equations that frankly, are over our heads as we did not get take more than two years of physics and two years of calculus, but the thrust of most of them is that both the claw grip and backwards walking create a more circular motion that moves the liquid around the cup rather than careening into the sides.

Han’s paper, released in the May issue of Achievements in the Life Sciences, has been a long time coming apparently. He gave a TED talk on the same topic way back in September.  


While you probably won’t be walking to your next meeting backwards, but maybe try altering your grip and see if you can’t keep your shirt clean. 


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