If you do not feel well after a night of low sleep, you may want to consider dehydration as a cause – not just a lack of sleep – and drink more water, according to a new study published in the journal SLEEP.
The study found that people who slept only six hours a night, instead of the eight recommended, were more likely to dehydrate.
Dehydration can affect many of the body's systems and functions, including knowledge, mood, physical performance, and more. Long-term or chronic dehydration can lead to more serious problems, such as the highest risk of urinary tract and kidney infections.
For the study, researchers at the University of Pennsylvania noted that sleep affected the condition of hydration and the risk of dehydration in American and Chinese adults. Participants who reported six hours of sleep had significantly more concentrated urine and 16 to 59% higher chances of not being adequately hydrated compared to those who slept eight hours on a regular basis at night.
The reason was linked to how the body's hormonal system regulates hydration.
The hormone vasopressin is released to help regulate the hydration status of the body. It is released throughout the day, as well as during nighttime sleep, which researchers have focused on.
"Vasopressin is released as quickly as it is later in the sleep cycle," lead author Dr. Asher Rosinger, assistant professor of biomedical behavior at Penn State. "So if you wake up earlier, you might lose the window where more hormone is released, causing a disruption in body hydration."
Two adult samples were analyzed through the National Health and Nutrition Survey and a sample was analyzed through the Chinese study Kailuan. A total of three samples included more than 20,000 people.
Participants reported their sleep habits and also provided urine samples that were analyzed by biomarkers for hydration.
All data are observable from both cross-sectional studies or a cross-sectional wave of a cohort study. Therefore, the results of the association should not be considered causative.
Future research should use the same methodology in different places and look at this relationship longitudinally over a week to understand the state of sleep and hydration, Rosinger said.
In conclusion, researchers suggest that hydration should be at the forefront of your mind the first thing in the morning after a low night's sleep.
"If you only take six hours a night sleep, it can affect your hydration status," Rosinger said. "This study shows that if you do not have enough sleep and you feel bad or tired the next day, you drink extra water."
Source: Penn State