Science has officially proven why a cold beer tastes so good on a warm summer day.
A study shows that cold and carbonated beverages actually quench thirst better. As the researchers put it: "Thirsty humans often prefer beverages that are both cold and carbonated including: mineral waters, seltzer, sodas, and beers." That may seem obvious, but no one knew why until now. The study shows that it all comes down to the chill and the bubbles—and, yes, in case you were wondering, beer is considered to be naturally carbonated, thanks to the fermentation process.
The research was conducted by a group of scientists from the Monell Chemical Senses Center in Philadelphia; the institution bills itself as "the world's only independent, nonprofit, scientific institute dedicated to interdisciplinary basic research on the senses of taste and smell."
In the study—which, it should be noted, was funded in part by the Japanese beer company Suntory—98 people between the ages of 20 and 50 were asked to abstain from liquid and food overnight and then head into the lab in the morning. There, they were given a small breakfast of white toast and jelly and put in a room to "rest." When asked to rate their thirst at that point, the participants all said it was "strong." Then, each participant was given five minutes to drink 13-and-a-half ounces of water, which varied: Some of the participants got water that was room-temperature, others cold, some water was carbonated, and some was not. After a short rest, the participants were allowed to drink as much room-temperature, non-carbonated water as they wanted. All quantities were measured.
Bottom line: Cold water reduced thirst more than room-temperature water did, and adding carbonation to a cold beverage made it even more thirst-quenching. Experiment variations to add astringency (as in tea), sweetness, and mild acidification had no effect. In the end, cold and carbonated won the game. A second experiment by the same researchers showed that using menthol to simulate a cooling sensation will also make people think their thirst is quenched faster than it is by a non-mentholated, room-temperature beverage.
Where do we go with this information? Well, the scientists are not exactly telling us to drown our thirst in an ice-cold Pepsi henceforth. Instead, they say this experiment—the results of which are being published in the journal Plos One—is just the beginning. The thing is that thirst is relieved long before your body actually absorbs the liquid you have consumed and the actual signals that your body uses to make you stop drinking still remain a mystery.
"Our data also have implications for groups who are known for clinical under-hydration, such as laborers, soldiers, and the elderly, possibly due to their ignoring or cognitively mishandling important sensory cues that guide thirst and its quenching," the study says.
Evidently, a cold beer is not the best answer for everyone.