You have heard these directives countless times. Drink sufficient water. Stay hydrated. Don’t let yourself become too thirsty. Drinking adequate amounts of water is not only important during the sometimes scorching days of summer; it is essential to remain hydrated throughout the year.
According to the European Hydration Institute, water plays a crucial role in the maintenance of life. Water is found in all of the body’s cells; about 60 percent of a man’s body and 50 to 55 percent of a woman’s body is water. Muscles and the brain are about 75 percent water; blood and kidneys are about 81 percent. Water provides cushioning and lubrication to the joints, and it “transports nutrients and carries waste away from the body cells.” Water even plays a role in regulating the body’s temperature; it redistributes body heat and cools the body by perspiring. 1
While water requirements vary from person to person, larger people need more water than smaller people, and people who exercise require more water than people who are inactive. Of course, weather conditions influence water needs. People tend to drink more water when temperatures are elevated. Meanwhile, people continuously lose water from breathing, sweating, and the elimination of urine. So, people need a regular intake of water. When the body has an insufficient amount of water to function properly, it is dehydrated. Symptoms of dehydration include muscle weakness, rigidity or tremors, confusion, hallucinations, delirium, abnormal respiration, and in severe cases, death. 2
It should be parenthetically noted that people who drink too much water may also become ill. Their electrolytes may become imbalanced, a condition known as hyponatremia, which has the potential to be life-threatening.
In a study published in 2014 in Nutrición Hospitalaria, researchers from Mexico wanted to learn more about the effects of hydration on performance during spinning, a type of vigorous biking. The cohort consisted of 12 men and nine women; these amateur athletes participated in three controlled, randomly assigned hydration protocols (no fluid, plain water, or sports drink) during three different sessions of 90 minutes of spinning. The researchers found that exercising without the intake of fluids triggered physical stress in men and women. “Both men and women had higher values for body temperature, mean blood pressure and heart rate during the exercise without fluid replacement, confirming that dehydration provokes physical stress.” If sufficient fluids are consumed, this physical stress may be avoided. “Consumption of plain water is sufficient for preventing physical stress in both genders, provided that an adequate volume is consumed to replace the loss of body fluid caused by sweating.” 4
In a crossover study, published in 2012 in the Journal of Nutrition, researchers from France and several locations in the United States examined the association between mild dehydration and moods in healthy young women. The cohort consisted of 25 females; they all participated in three day-long, placebo-controlled experiments. Each day, there were different states of hydration—exercise-induced hydration with no diuretic, exercise-induced hydration with diuretic, and normal state of hydration. A number of different experimental assessments were made. While dehydration did not appear to affect the women’s cognitive performance, the researchers found that it had other consequences. When compared to their results when they were adequately hydrated, the mildly dehydrated women had reduced vigor and more fatigue and mood disturbances.
They found it harder to concentrate, and they experienced an increase in their perception of task difficulty. The researchers concluded that “in healthy young women, mild levels of dehydration result in adverse changes in key mood states such as vigor and fatigue as well as increased headaches and difficulty concentrating, without substantially altering key aspects of cognitive performance.” 6
Though we all hope to be sufficiently hydrated, consuming too few fluids, especially water, is very common. People tend to lead busy lives. Remembering how much water we drink is just one more thing to fit into an overscheduled life. But, a few suggestions may make dehydration less likely.
While there are many studies on health problems related to the consumption of inadequate water and other fluids, there are relatively few studies on barriers that help prevent the intake of these fluids. In a study published in 2013 in BMC Public Health, researchers from Seattle, Washington, wanted to learn more about the prevention and treatment of heat-related illnesses in Latino farmworkers. One of these concerns is dehydration from the intake of too few fluids, especially water. The researchers conducted three semistructured Spanish-language focus group discussions with a total of 35 Latino farmworkers in Central Washington. Sixty percent of the workers were male; only 19 percent had more than a ninth grade education. All but one of the workers had become ill from heat. Yet, they failed to drink a sufficient amount of water to prevent heat-related illness. While they acknowledged that water was “the healthiest beverage to consume at work,” the participants reported drinking soda, energy drinks, and coffee. Why not drink more water? The participants cited a variety of reasons. These ranged from not wanting to interrupt their work to worry about the safety and cleanliness of the water. Some wanted to sweat more in order to lose weight. One person said, “sometimes we don’t drink water so we won’t have to use the bathroom, because it’s too far away.” 8
In a study published in 2013 in Salud Pública de México (Public Health in Mexico), researchers from Morelos, Mexico, wanted to determine what low-income adults in Cuernavaca, Mexico, knew about the consumption of water. A total of eight focus groups were conducted with either all men or all women; the men and women were between 21 and 59 years old. While some people praised water and said that it was refreshing, people also noted that water caused stomach upset, headaches, and other medical problems. The researchers suggest that these negative notions may create barriers for the consumption of water. 9
1. European Hydration Institute, www.europeanhydrationinstitute.org.
3. Roberta Fadda, Gertrude Rapinett, Dominik Grathwohl et al., “Effects of Drinking Supplementary Water at School on Cognitive Performance in Children,” Appetite 59, no. 3 (2012): 730-37.
4. Arnulfo Ramos-Jiménez, Rosa Patricia Hernández-Torres, Abraham Wall-Medrano et al., “Gender- and Hydration-Associated Differences in the Physiological Response to Spinning,” Nutrición Hospitalaria 29, no. 3 (2014): 644-51.
5. Nathalie Pross, Agnès Demazières, Nicolas Girard et al., “Effects of Changes in Water Intake on Mood of High and Low Drinkers,” PLoS ONE 9, no. 4 (2014): e94754.
6. Lawrence E. Armstrong, Matthew S. Ganio, Douglas J. Casa et al., “Mild Dehydration Affects Mood in Healthy Young Women,” Journal of Nutrition 142 (2012): 382-88.
7. Stephen J. Onufrak, Sohyun Park, Joseph R. Sharkey, and Bettylou Sherry, “The Relationship of Perceptions of Tap Water Safety with Intake of Sugar-Sweetened Beverages and Plain Water Among U. S. Adults,” Public Health Nutrition 17, no. 1 (2012): 179-85.
8. Michelle Lam, Jennifer Krenz, Pablo Palmández et al., “Identification of Barriers to the Prevention and Treatment of Heat-Related Illness in Latino Farmworkers Using Activity-Oriented, Participatory Rural Appraisal Focus Group Methods,” BMC Public Health 13 (2013): 1004+.
9. J. Espinosa-Montero, M. F. Aguilar-Tamayo, E. A. Monterrubio-Flores, and S. Barquera-Cervera, “Knowledge About Consumption of Plain Water in Adults of Low Socioeconomic Status of the City of Cuernavaca, México,” Salud Pública de México (Public Health in Mexico) 55, Supplement 3 (2013): 423-30.
Armstrong, Lawrence E., Matthew S. Ganio, Douglas J. Casa et al. “Mild Dehydration Affects Mood in Healthy Young Women.” Journal of Nutrition 142 (2012): 382-88.
Espinosa-Montero, J., M. F. Aguilar-Tamayo, E. A. Monterrubio-Flores, and S. Barquera-Cervera. “Knowledge About Consumption of Plain Water in Adults of Low Socioeconomic Status of the City of Cuernavaca, México.” Salud Pública de México (Public Health in Mexico) 55, Supplement 3 (2013): 423-30.
Fadda, Roberta, Gertrude Rapinett, Dominik Grathwohl et al. “Effects of Drinking Supplementary Water at School on Cognitive Performance in Children.” Appetite 59, no. 3 (2012): 730-37.
Holdsworth, J. E.. “The Importance of Human Hydration: Perceptions Among Healthcare Professionals Across Europe.” Nutrition Bulletin 37 (2012): 16-24.
Lam, Michelle, Jennifer Krenz, Pablo Palmández et al. “Identification of Barriers to the Prevention and Treatment of Heat-Related Illness in Latino Farmworkers Using Activity-Oriented, Participatory Rural Appraisal Focus Group Methods.” BMC Public Health 13 (2013): 1004+.
Lindseth, Paul D., Glenda N. Lindseth, Thomas V. Petros et al. “Effects of Hydration on Cognitive Function of Pilots.” Military Medicine 178, no. 7 (2013): 792-98.
Liu, J., X. Hu, Q. Zhang et al. “Knowledge, Attitude, and Practice on Drinking Water of Primary and Secondary Students in Shenzhen.” Wei Sheng Yan Jiu (Journal of Hygiene Research) 43, no. 3 (2014): 419-22.
Onufrak, Stephen J., Sohyun Park, Joseph R. Sharkey, and Bettylou Sherry. “The Relationship of Perceptions of Tap Water Safety with Intake of Sugar-Sweetened Beverages and Plain Water Among U. S. Adults.” Public Health Nutrition 17, no. 1 (2012): 179-85.
Pawson, Chris, Mark R. Gardner, Sarah Doherty et al. “Drink Availability is Associated with Enhanced Examination Performance in Adults.” Psychology Teaching Review 19, no. 1 (2013): 57-66.
Pross, Nathalie, Agnès Demazières, Nicolas Girard et al. “Effects of Changes in Water Intake on Mood of High and Low Drinkers.” PLoS ONE 9, no. 4 (2014): e94754.
Ramos-Jiménez, Arnulfo, Rosa Patricia Hernández-Torres, Abraham Wall-Medrano et al. “Gender- and Hydration-Associated Differences in the Physiological Response to Spinning.” Nutrición Hospitalaria 29, no. 3 (2014): 644-51.
Senterre, Christelle, Michèle Dramaix, and Isabelle Thiébaut. “Fluid Intake Survey Among Schoolchildren in Belgium.” BMC Public Health 14 (2014): 651+.
European Hydration Institute. www.europeanhydrationinstitute.org .