The Mental Effects of Dehydration

Recently Daniel Chong, a 23-year-old college student made the news because he was mistakenly left alone in a holding cell by the DEA in San Diego, California. During his 5 days in the holding cell, he had no food or water.

After days of isolation and dehydration, Chong said he tried to commit suicide by breaking his glasses and using the shards. He carved “Sorry Mom” on his arm.

His lawyer says he “had Japanese cartoon characters telling him where to find water.”

“I had to do what I had to do to survive….I hallucinated by the third day,” Chong said. “I was completely insane.”

While most people will not experience as severe of a case of dehydration as Donald Chong did (think runners and characters in old Westerns), many people do experience minor dehydration from not drinking enough fluids. Effects of dehydration can be seen when there is only a 1 to 2 percent loss of water weight in the body.

Symptoms of dehydration can begin quickly because the body does not store water. Once it is used, it is gone and must be replaced. If the water is not replaced, the body starts taking water from the cells in the body and brain. Mental effects of dehydration occur because the brain tissues shrink when the body removes water from the brain cells in an attempt to survive.

Dehydration can cause symptoms ranging from mild irritability to severe hallucinations. Symptoms of mild dehydration often go unrecognized. It is not until dehydration is severe, that the symptoms are worrisome enough to cause a person to seek treatment.

Mild Dehydration Symptoms

People can be mildly dehydrated and not know it. This is because they are drinking fluids throughout the day, but not as much as their bodies need. In mild cases of dehydration, irritability, anxiety, and fatigue can develop. People who are dehydrated may feel anxious for no apparent reason. They may have difficulty thinking clearly and solving everyday life problems. Minor dehydration can also cause people to perceive tasks as harder than they actually are, according to a 2012 study published in the “Journal of Nutrition.” Mild dehydration can be treated by increasing fluid intake.

Severe Dehydration Symptoms

If a person does not ingest fluids for long enough, confusion sets in. The signs of confusion can resemble the symptoms of dementia. Dehydration often goes undetected in elderly people because the signs of confusion are commonly mistaken for signs of dementia. Hallucinations can develop if dehydration gets severe enough. The hallucinations can be visual or auditory. In severe hallucinations, the person may be unable to differentiate between reality and the hallucinations. It is a medical emergency once confusion and hallucinations begin, and hospital treatment is necessary. If medical treatment is not given, the condition can be fatal.


  1. DEA Ignored All My Cries: Student
    NBC San Diego By Sarah Grieco and Rory Devine
    Thursday, May 3, 2012
  2. Student left in cell for 5 days wants $20 million from DEA
    Los Angeles Times
    May 3, 2012
  3. Standford School of Medicine: What Other Conditions May Mimic Dementia?
  4. University of Connecticut: Even Mild Dehydration Can Alter Mood
  5. Nutrition Reviews 64(10 Pt 1):457-64; Hydration and Cognitive Function in Children; D’Anci KE, Constant F, Rosenberg IH; 2006
  6. Human Brain Mapping 30(1):291-8; Effects of Acute Dehydration on Brain Morphology in Healthy Humans; Kempton MJ et al; 2009

Posted by CJ Newton, MA, Editor on May 14, 2012 at 05:00 AM

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