Have you ever noticed that as soon as you finish an ice cream cone, you’re parched? All the sugar is making your head spin, and the back of your mouth gets dry. Ice cream is supposed to be refreshing, especially when it’s hot out, so feeling dehydrated immediately after eating it is a little bit confounding, to say the least.
Even the industry’s in on it. What’s located right behind your local scoop shop’s counter where all the flavors are on display? A cooler full of water bottles. So what’s going on here — is there truly a some form of chemical reaction at play?
Research shows that eating something sweet triggers your liver to release a hormone (called FGF21),” says Brierley Horton, MS, RD. “Once that hormone hits your bloodstream, it travels to your hypothalamus and essentially tells your brain you’re thirsty. Interestingly, drinking alcohol will stimulate this ‘conversation’ between liver and brain, as will a high-fat/low-carb diet, such as the ketogenic diet.”
It’s the same sensation behind why you may crave a glass of milk with cookies or a piece of cake. Essentially, your body’s trying to balance out all that sugar you just ingested. However, sugar may not be the only ingredient that’s to blame for the intense thirst that ensues as you polish off a serving a sweet, cooling ice cream.
“[Salt] is typically used in making ice cream, and it could leave you feeling parched, too, and boost your desire to drink some H2O,” Horton says. “That said, the mechanism by which sweets trigger thirst is not the case for salt and its ability to have you reaching for a glass of ice water.”
So no, post-ice cream thirst isn’t in your head; rather, it’s in your blood and your brain, with sugar and salt setting off all the signals.
