What Happens When Kids Don't Drink Enough Water?

As many as 1 in 5 kids don’t drink water regularly. Find out what they’re downing instead (and what they’re risking because of it).

by Lara DeSanto Health Writer

When kids don’t drink water regularly, they’re more likely to down sugary drinks in its place, finds a new study in the Journal of American Medical Association Pediatrics. Over time, that added sugar can contribute to weight gain, diabetes, heart disease, and other serious health problems.

In fact, researchers found that a whopping 20% of kids don’t drink any water at all throughout the day. What’s more, those kids end up consuming about 200 calories per day from sweet drinks alone, twice as much as their water-drinking peers. (Researchers took data from the National Health and Nutrition Examination Survey, which includes information on 8,400 kids between age 2 and 19.)

"Kids should consume water every single day, and the first beverage option for kids should be water," said lead author Asher Rosinger, Ph.D., assistant professor of biobehavioral health and director of the Water, Health, and Nutrition Lab at Penn State in a press release. "Because if they're not drinking water, they're probably going to replace it with other beverages that are less healthy and have more calories."

But what exactly counts as a sugary drink? Anything that has added sugar, like soda, fruit cocktails, sports drinks, energy drinks, and sweetened coffee or tea drinks, says Dr. Rosinger.

While 200 extra calories may not seem like a lot, they can add up fast, said Dr. Rosinger. "What you have to remember is that an extra 3,500 calories equals one pound of weight gain," Dr. Rosinger said. "So if you're not compensating for those extra calories, then over a month, you can potentially gain a pound." Over the course of several months, kids could gain a significant amount of weight.

Just as concerning, past research has shown that not all calories are created equal. In fact, calories from added sugar are more likely to increase your risk of heart disease, diabetes, and other issues, compared with calories from other sources.

Does this mean you need to totally ban everything except water and milk from your household? Well, that’s up to you — in moderation, a sweet drink may make a good treat. But the U.S. Department of Agriculture does recommend that no more than 10% of any person’s daily calories come from added sugars. If you’re an adult eating 2,000 calories per day, that means you should limit your sugar to 200 calories — about 12 teaspoons (that’s a bit more than one can of cola). In the study, kids who drank no water often blew past this recommended limit.

It may not be entirely within kids’ control to get enough (or any) water throughout the day, however, researchers noted. In some parts of the country, people don’t trust that their water is safe to drink — look at the crisis in Flint, Michigan, for example.

"Water insecurity is a growing problem in the U.S., so we need to keep that in mind as important context, especially when it comes to parents who may be giving their kids soda or juice because they distrust the water,” said Dr. Rosinger in the press release.

Generally, though, most kids in the U.S. have access to clean water. The goal, then, is to help shift the balance so water wins out over soda. Here’s what to do:

  • Start early. If your kids are still young, stick to water and milk as much as possible, saving lemonade and soda for special occasions. It’s much easier to get your teen hooked on LaCroix if they’ve never had a chance to become addicted to Sprite.

  • Keep an eye on juice. One-hundred percent fruit juice doesn’t have added sugar—but it’s still high in natural sugars.

  • Opt for milk. Milk has eight grams of protein per cup, which will fill your child up more than juice anyway, without the added sugar and calories, says registered dietitian and HealthCentral writer Carmen Roberts. And, yes, it’s totally ok to add a squirt of chocolate syrup.

  • Be patient. The process of cutting down on sugary drinks in your household won’t happen overnight. If your kid is in the no-water camp, start by adding a little water to his regular lemonade or soda. After a few days, add a little more. As you make more progress, you can switch to seltzer and add a splash of juice for a healthier “soda.” There may be complaints along the way, but if you stay the course, your kid can kick his sugar habit.

Lara DeSanto
Meet Our Writer
Lara DeSanto

Lara is a former digital editor for HealthCentral, covering Sexual Health, Digestive Health, Head and Neck Cancer, and Gynecologic Cancers. She continues to contribute to HealthCentral while she works towards her masters in marriage and family therapy and art therapy. In a past life, she worked as the patient education editor at the American College of OB-GYNs and as a news writer/editor at WTOP.com.