Sorry, Holding Warm Coffee Won't Make You Nicer

A 2008 study from Yale University psychology professors found that holding something warm, like a cup of hot coffee, makes a person more likely to demonstrate generosity. The study received wide attention eleven years ago, and pops up every so often in the years since. But a new study tried to replicate that 2008 study’s results, and found something different. Well, more accurately, the new study found nothing at all.

The researchers behind the revisited study explain that it’s worth retesting the whole hot-coffee-makes-you-generous thing because the original had some flaws. The 2008 study had a small sample size—it was done twice, with 41 and 53 people—and those tested were all college students from one town in upstate New York, rather than a representative sample of the population at large.

The new researchers simply re-did the test, but fixing those problems by using a larger sample size—over three times more people—and a more diverse group of participants. What they found is that, instead of a small change in generosity, there were “near-zero effects” from holding either a hot or a cold beverage.

Even with this new study, the conclusion formed by the scientists themselves isn’t “hot coffee does not make you generous,” but that there is “substantially more evidence for the null hypothesis of no effect than for the original physical warmth priming hypothesis.” In other words, nobody proved this isn’t true; there is no proof.

The new research indicates, by changing variables that might have thrown off the initial study, that it’s more likely that holding a cup of hot coffee doesn’t change your outlook. It does, however, warm your hands, which is nice on a cold winter day.