Your brain literally shrinks in volume when it doesn’t get enough water, a growing body of research has shown.
When we’re dehydrated, moodiness, decreased energy levels, and perceiving tasks to be more difficult can come with brain shrink.
In fact, a study on teenagers by the Centre for Neuroimaging Sciences in London found that when subjects were dehydrated, their brains had to work harder than when they weren’t dehydrated. The findings suggest that prolonged states of reduced water intake may adversely impact executive functions such as planning and visual-spatial processing.
“The brain is extremely sensitive to even small changes in the amounts of ions like sodium and potassium found in your body’s fluids,” scientist and researcher Harris Lieberman explained to Shape magazine, adding that even mild dehydration can be detrimental to the proper functioning of your brain.