Most American children and teenagers aren't drinking enough fluids, and that's leaving them mildly dehydrated, according to a new study. In fact, one-quarter of a broad cross-section of children ages 6 to 19 apparently don't drink any water as part of their fluid intake.
The Harvard scientists who turned up the finding were initially looking into the consumption of sugary drinks in schools and looking for ways to steer children toward water instead — a much healthier beverage.
Along the way, they noticed that "kids weren't really drinking that much fluid," says postdoctoral researcher Erica Kenney at Harvard's T.H. Chan School of Public Health. She wondered if that was posing any problems for them.
So she and her colleagues dug into data from the National Health and Nutrition Examination Survey, which gathers an amazing amount of information from study participants, including chemical tests of their urine. Those urine tests reveal whether people are adequately hydrated — people who don't take in enough water have darker, saltier urine.
The researchers report Thursday in the American Journal of Public Health that more than half of the several thousand students studied between 2009 and 2012 were at least a bit dehydrated.
"This doesn't mean we're saying kids are dropping like flies or that they're very seriously dehydrated and need to go to the hospital or anything like that," Kenney says. But even mild dehydration can affect children's fatigue levels, mood and possibly their ability to learn, she says.
"It was astounding to me," Kenney says, that so many children said they drink no water at all. "And even among the kids who were drinking water — they weren't drinking very much of it."
The Institute of Medicine says children and teenagers should consume about two to three quarts of water a day (1.7 to 3.3 liters, the IOM says), depending on age, size and sex. Adolescent boys generally need to drink more water than girls do, research suggests.
"That's total water, so that can be from any beverages — any water that's in your food like soups, juicy fruits and vegetables, things like that," Kenney says.
And while kids fall short, dehydration is an easy problem to fix: Just get them to drink more water throughout the day. But Kenney says it's not quite as simple as it seems.
Especially in cities, "a lot of schools have struggled with providing tap water to kids because of concerns about older plumbing infrastructure and concerns about lead," she says.
Some schools offer jugs of bottled water, but that's expensive and time-consuming to maintain.
Kenney says some school programs aimed at reducing consumption of sugary drinks are now making water more accessible and appealing in the cafeteria — adding a soda-fountain style dispenser for water, for example. Those mealtime programs, she says, can help on the dehydration front, as well.
DAVID GREENE, HOST:
And some more health news now, specifically why it is important to stay hydrated. A new study says children and teens in America are not drinking enough fluids and that is leaving them mildly dehydrated. The researchers say hydration is important, not just for physical performance, but also for short-term memory, fatigue and mood. NPR's Richard Harris has more.
RICHARD HARRIS, BYLINE: Scientists at Harvard have been exploring ways to get more water to schoolchildren in order to give them a healthier option than drinking sugary beverages, which increase the risk of diabetes and obesity.
ERICA KENNEY: We were also noticing, you know, kids weren't really drinking that much fluid. And we kind of thought, I wonder if this is actually a problem.
HARRIS: So postdoctoral researcher Erica Kenney and her colleagues dug into a national health survey that gathers an amazing amount of information from volunteers, including chemical tests of their urine. People who don't drink enough fluids have saltier urine. And the researchers now report, in the American Journal of Public Health, that more than half of these American kids, aged 6 to 19, were at least a bit dehydrated.
KENNEY: This doesn't mean that we're saying that kids are dropping like flies or that they're very seriously dehydrated and need to go to the hospital or anything like that. But a lot of kids are going through their day in this state of mild dehydration. And that could be potentially affecting how well they're feeling during the day.
HARRIS: And at - one statistic that really stood out for me was a large percentage of kids apparently never drink water.
KENNEY: I know, right? Like, about a quarter actually are never drinking any water. And, yeah, it was astounding actually to me. And even among the kids who were drinking water, they weren't drinking very much of it either.
HARRIS: The Institute of Medicine says children and teenagers should consume two to three quarts of water a day, depending upon age and sex. Adolescent boys need more than girls.
KENNEY: And that's total water. So that can be from any beverages, any water that's in your foods, like soups and, you know, juicy fruits and vegetables, things like that.
HARRIS: And while kids fall short, dehydration is an easy problem to fix - just get them to drink more water throughout the day. But Kenney says it's not quite as simple as it seems.
KENNEY: In some - especially urban public school districts in the country - a lot of schools have kind of struggled with providing tap water to kids because of concerns about older plumbing infrastructure and concerns about lead.
HARRIS: Kenney says some schools are figuring out ways to make water more accessible and more appealing in the cafeteria. Those mealtime programs are designed to give kids an alternative to sugary drinks, but it turns out they can help on the dehydration front as well. Richard Harris, NPR News. Transcript provided by NPR, Copyright NPR.