Cranky today? Even mild dehydration can alter our moods
Most people only think about drinking water when they are thirsty; but by then it may already be too late.
Even mild dehydration can alter a person's mood, energy level, and ability to think clearly, according to two studies recently conducted at the University of Connecticut's Human Performance Laboratory.
The tests showed that it didn't matter if a person had just walked for 40 minutes on a treadmill or was sitting at rest the adverse effects from mild dehydration were the same. Mild dehydration is defined as an approximately 1.5 percent loss in normal water volume in the body.
The test results affirm the importance of staying properly hydrated at all times and not just during exercise, extreme heat, or exertion, says Lawrence E. Armstrong, one of the studies' lead scientists and a professor of physiology in UConn's Department of Kinesiology in the Neag School of Education.
"Our thirst sensation doesn't really appear until we are 1 [percent] or 2 percent dehydrated. By then dehydration is already setting in and starting to impact how our mind and body perform," says Armstrong, an international expert on hydration who has conducted research in the field for more than 20 years. "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."
Separate groups of young women and men were tested. Twenty-five women took part in one study. Their average age was 23. The men's group consisted of 26 men with an average age of 20. All of the participants were healthy, active individuals, who were neither high-performance athletes nor sedentary typically exercising for 30 to 60 minutes per day.
Each participant took part in three evaluations that were separated by 28 days. All of the participants walked on a treadmill to induce dehydration, and all of the subjects were hydrated the evening before the evaluations commenced. As part of the evaluation, the subjects were put through a battery of cognitive tests that measured vigilance, concentration, reaction time, learning, memory, and reasoning. The results were compared against a separate series of tests when the individuals were not dehydrated.
In the tests involving the young women, mild dehydration caused headaches, fatigue, and difficulty concentrating, according to one of the studies, which appears in the February issue of The Journal of Nutrition. The female subjects also perceived tasks as more difficult when slightly dehydrated, although there was no substantive reduction in their cognitive abilities.
In the tests involving the young men, mild dehydration caused some difficulty with mental tasks, particularly in the areas of vigilance and working memory, according to the results of the second UConn study. While the young men also experienced fatigue, tension, and anxiety when mildly dehydrated, adverse changes in mood and symptoms were "substantially greater in females than in males, both at rest and during exercise," according to the study. The men's study was published in the British Journal of Nutrition in November 2011.
"Even mild dehydration that can occur during the course of our ordinary daily activities can degrade how we are feeling especially for women, who appear to be more susceptible to the adverse effects of low levels of dehydration than men," says Harris Lieberman, one of the studies' co-authors and a research psychologist with the Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine in Natick, Mass. "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."
Why women and men are so adversely affected by mild dehydration is unclear, and more research is necessary. But other research has shown that neurons in the brain detect dehydration and may signal other parts of the brain regulating mood when dehydration occurs. This process could be part of an ancient warning system protecting humans from more dire consequences, and alerting them to the need for water to survive.
In order to stay properly hydrated, experts like Armstrong recommend that individuals drink eight, 8-ounce glasses of water a day, which is approximately equivalent to about 2 liters of water. People can check their hydration status by monitoring the color of their urine. Urine should be a very pale yellow in individuals who are properly hydrated. Urine that is dark yellow or tan in color indicates greater dehydration. Proper hydration is particularly important for high-risk groups, such as the elderly, people with diabetes, and children.
Provided by University of Connecticut
- Dehydration Affects Mood, Not Just Motor Skills Nov 24, 2009 | not rated yet | 0
- Brain malfunction explains dehydration in elderly Dec 18, 2007 | not rated yet | 0
- Milk better than water to rehydrate kids: study Aug 17, 2011 | not rated yet | 0
- Professional sports persons should drink more water Oct 19, 2010 | not rated yet | 0
- Dangerous heat leaves kids at risk for dehydration Jun 08, 2011 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
Classical and Quantum Mechanics via Lie algebras
Apr 15, 2011 I'd like to open a discussion thread for version 2 of the draft of my book ''Classical and Quantum Mechanics via Lie algebras'', available online at http://lanl.arxiv.org/abs/0810.1019 , and for the...
- More from Physics Forums - Independent Research
More news stories
Bed sharing with parents is linked to a fivefold increased risk of sudden infant death syndrome (SIDS), even when the parents are non-smokers and the mother has not been drinking alcohol and does not use illegal drugs, according ...
Health 8 hours ago | 1.3 / 5 (3) | 0
Doctors tell people with a heart-zapping device in their chests to give up intense sports like basketball and soccer in favor of golf or bowling. But lots of patients ignore that advice—and now new research is challenging ...
Health 8 hours ago | not rated yet | 0
Little is known about the effect of physical education (PE) on child weight, but a new study from Cornell University finds that increasing the amount of time that elementary schoolchildren spent in gym class reduces the probability ...
Health 10 hours ago | not rated yet | 0
Living near a major roadway during the prenatal period is associated with an increased risk of respiratory infection developing in children by the age of 3, according to a new study from researchers in Boston.
Health 12 hours ago | not rated yet | 0
People who are consistently exposed to both wood smoke and tobacco smoke are at a greater risk for developing chronic obstructive pulmonary disease (COPD) and for experiencing more frequent and severe symptoms of the disease, ...
Health 12 hours ago | not rated yet | 0
Early-life exposure to traffic-related air pollution was significantly associated with higher hyperactivity scores at age 7, according to new research from the University of Cincinnati (UC) and Cincinnati Children's Hospital ...
2 hours ago | not rated yet | 0 |
(Medical Xpress)—A research team, led by Jeremy Barr, a biology post-doctoral fellow, unveils a new immune system that protects humans and animals from infection.
8 hours ago | 4.6 / 5 (12) | 3 |
New research suggests that a compound abundant in the Mediterranean diet takes away cancer cells' "superpower" to escape death. By altering a very specific step in gene regulation, this compound essentially re-educates cancer ...
11 hours ago | 4.8 / 5 (11) | 2 |
Bacteria resistant to the antibiotic colistin are also commonly resistant to antimicrobial substances made by the human body, according to a study in mBio, the online open-access journal of the American Society for Microb ...
2 hours ago | 5 / 5 (1) | 0
Researchers have pinpointed a catalytic trigger for the onset of Alzheimer's disease – when the fundamental structure of a protein molecule changes to cause a chain reaction that leads to the death of neurons ...
11 hours ago | 5 / 5 (3) | 0 |
Salamanders' immune systems are key to their remarkable ability to regrow limbs, and could also underpin their ability to regenerate spinal cords, brain tissue and even parts of their hearts, scientists have ...
11 hours ago | 4.8 / 5 (6) | 2 |