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Why Ice Cream Might Make You Thirsty

Why does ice cream make some people thirsty?

Why does ice cream make some people thirsty? We asked around the office to see if this was a common affliction, and about half the people said that yes, ice cream does leave a parched mouth. (Most also said they had thought that they were alone in their thirstiness.)

When in doubt, we often look to our science editor for explanation. He told us that sweet foods (like ice cream) behave much like salty foods when eaten in quantity. As ice cream is digested and sugar is rapidly absorbed into the blood, the concentration of sugar in the blood becomes higher than the concentration of sugar in the body’s other cells. Since nature abhors an imbalance, osmosis kicks in, forcing water out of the cells, through membranes, and into the blood to equalize the relative concentrations of sugar. The brain senses that the cells are losing moisture, and the craving for a glass of water kicks in.

THE BOTTOM LINE: You’re not imagining that post–ice cream thirst. Go ahead and treat yourself to a tall drink of water.

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