Yes: Dehydration Affects Your Mental Health

Water and Mental Health

By and large, the only time we pine for a drink of water is when we feel thirsty. However, when it comes to your mental health, you may want to be a lot more proactive. Studies show that even mild dehydration can have a significant impact on your mood, energy, and even your ability to think clearly.

Research conducted at the University of Connecticut’s Human Performance Laboratory confirmed an array of negative effects resulting from dehydration including  "degraded mood, increased perception of task difficulty, lower concentration, and headache symptoms."


The fact is that the human brain is comprised of about 75% water. Dehydration slows circulation, which results in less oxygen travelling to your entire body - including your brain. Scientists suggest that the thirst impulse is a part of the body's complex warning system and should not be ignored even at mild levels. Dehydration can impair cognitive function, at extreme levels can lead to delirium, unconsciousness and even coma.

Results from the study showed that whether a person exercised on a treadmill for 30-40 minutes or remained in a stationary position - the negative effects from mild dehydration were the same. Lawrence E. Armstrong, professor of physiology in UConn’s Department of Kinesiology, says "The test results affirm the importance of staying properly hydrated at all times and not just during exercise, extreme heat, or exertion."

“Dehydration affects all people, and staying properly hydrated is just as important for those who work all day at a computer as it is for marathon runners, who can lose up to 8 percent of their body weight as water when they compete”, says Armstrong.

The trial involved healthy women and men in their early 20's who endured a series exercises designed to induce dehydration. Shortly thereafter, the participants took a series of cognitive tests to measure learning, concentration, reaction time, and memory. Researchers compared those results to test results from when the participants were not dehydrated.

The science behind the findings is complex, but research has shown that our brains have the ability to detect dehydration and may be signaling the parts of our brain that affect mood regulation.

Results among the women revealed that mild dehydration resulted in fatigue, headaches, and decreased ability to concentrate. The men experienced challenges in completing mental task involving alertness and memory and reported instances of tension, anxiety, and fatigue.  According to research psychologist Harris Lieberman, one of the studies’ co-authors, “In both sexes these adverse mood changes may limit the motivation required to engage in even moderate aerobic exercise. Mild dehydration may also interfere with other daily activities, even when there is no physical demand component present.”

Even young are affected by this dynamic. In fact, the most consistent findings on the subject have been through studies involving children. A series of studies focused on young people age 7 to 9 revealed both improved memory and attention after hydrating. 

The science behind the findings is complex, but research has shown that our brains have the ability to detect dehydration and may be signaling the parts of our brain that affect mood regulation. It could all be as simple as the body's innate warning system that both protects us and alerts us to the need for water to survive and thus puts us in a mental state to conserve water and limit extra water loss through physical or mental activity.


We've heard it before, but it bears repeating. In order to stay properly hydrated, experts advise that we drink eight, 8-ounce glasses of water everyday - that's about 2 liters. Proper hydration is especially critical for older adults, children, and individuals with diabetes. Our bodies are complex, and we have to take a holistic approach in order to maximize our well-being. Staying hydrated by drinking enough water is a simple, but vital component of optimal physical, emotional, and mental health.