Asked by: Lucy Tuttle, Leeds
A 1997 study at the Yale School of Medicine found that the action of drinking is more thirst quenching than being rehydrated through a nasogastric tube. That’s because the physical sensation of drinking tells the brain that you are rehydrating. That sensation is enhanced if the temperature of the drink is hotter or colder than your mouth and throat, because the temperature-sensing nerves are stimulated as well as the touch sensitive ones. Cold also suppresses our sense of sweetness and commercial drinks allow for this, so drinking them lukewarm makes them excessively sweet.
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