Mild hydration commonly occurs throughout the day as people tend to their daily activities. A new study indicates that even mild levels of dehydration can impair sustained attention- but not other cognitive functions- in middle-aged and older adults. The corresponding study was published in the American Journal of Human Biology.
Research shows that poor hydration is linked to the biological acceleration of age, higher risk of chronic disease, and earlier mortality. However, studies have shown mixed results on how it may affect cognitive performance.
In the present study, researchers assessed how hydration status affects cognitive performance in middle-aged- older adults. To do so, they recruited 78 participants aged 47- 70 years old, and assessed their cognitive performance at hydration status at three points over a 3-month period.
At each assessment, between 29 and 39.1% of participants were dehydrated. The researchers ultimately found that the more dehydrated participants were, the worse they performed on a task assessing sustained attention. They noted however that dehydration had no significant affect on inhibition, working memory and cognitive flexibility.
“This suggests that if a person is, on a daily basis, drinking less water than their body needs, it may take them slightly longer to complete certain long tasks with slightly more errors,” said study author, Asher Rosinger, associate professor of biobehavioral health and anthropology and director of the Water, Health, and Nutrition Lab at The Pennsylvania State University, in a press release.
“It shows that in daily life when adults are not experimentally dehydrated- such as sitting in a sauna or going for an hour bike ride without drinking water- their cognitive performance on short tasks is not different than those who are better hydrated," he continued.
He added that its important for older adults to drink water regularly as it will improve their ability to maintain sustained attention, and may ‘give them a boost’ while at work or engaged in other daily activities.
Sources: Neuroscience News, American Journal of Human Biology