Growth Curve | Science News

Be a Champion for Science

Get your subscription to

Science News when you join.

Growth Curve

The inexact science of raising kids

Laura Sanders

Growth Curve


Growth Curve

For kids, daily juice probably won’t pack on the pounds

kid drinking juice

An analysis of existing studies linked daily juice drinking to very small amounts of extra weight in young children. The amount was so minuscule that it probably doesn’t matter, scientists say. The studies looked at only 100 percent fruit juice, not fruit cocktail drinks.

Sponsor Message

I’ve been to the playground enough times to know a juicy parenting controversy when I see (or overhear) one. Bed-sharing, breastfeeding and screen time are always hot-button issues. But I’m not talking about any of those. No, I’m talking about actual juice.

Some parents see juice as a delicious way to get vitamins into little kids. Others see juice as a gateway drug to a sugar-crusted, sedentary lifestyle, wrapped up in a kid-friendly box. No matter where you fall on the juice spectrum, you can be sure there are parents to either side of you. (Disclosure: My kids don’t drink much juice, simply because the people who buy their groceries aren’t all that into it. And juice is heavy.)

Scientific studies on the effects of juice have been somewhat sparse, allowing deeply held juice opinions to run free. One of the chief charges against juice is that it’s packed with sugar. An 8-ounce serving of grape juice, even with no sugar added, weighs in at 36 grams. That tops Coca-Cola, which delivers 26 grams of sugar in 8 ounces. And all of those extra sweet calories can lead to extra weight.

A recent review of eight studies on juice and children’s body weight, published online March 23 in Pediatrics, takes a look at this weight concern. It attempts to clarify whether kids who drink 100 percent fruit juice every day are at greater risk of gaining weight. After sifting through the studies’ data, researchers arrived at an answer that will please pro-juicers: Not really.

“Our study did not find evidence that consuming one serving per day of 100 percent fruit juice influenced BMI to a clinically important degree,” says study coauthor Brandon Auerbach of the University of Washington in Seattle.

The analysis found that for children ages 1 to 6, one daily serving of juice (6 to 8 ounces) was associated with a sliver of an increase in body mass index, or BMI. Consider a 5-year-old girl who started out right on the 50th percentile for weight and BMI. After a year of daily juice, this girl’s BMI may have moved from the 50th to the 52nd or 54th percentile, corresponding to a weight increase of 0.18 to 0.33 pounds over the year. That amount “isn’t trivial, but it’s not enough on its own to lead to poor health,” Auerbach says.

The results, of course, aren’t the final word. The analysis was reviewing data from other studies, and those studies came with their own limitations. For one thing, the studies didn’t assign children to receive or not receive juice. Instead, researchers measured the children’s juice-drinking behavior that was already under way and tried to relate that to their weight. That approach means that it’s possible that differences other than juice consumption could influence the results.

It’s important to note the distinction here between the 100 percent fruit juice in the studies and fruit cocktails, which are fruit-flavored drinks that often come with lots of added sugar. The data on those drinks is more damning in terms of weight gain and the risk of cavities, Auerbach says.

Also worth noting: The American Academy of Pediatrics recommends that kids between ages 1 and 6 get only 4 to 6 ounces of juice a day. That’s a smaller amount than many of the kids in the studies received. And the AAP recommends babies younger than 6 months get no juice at all.

In general, whole fruits, such as apples and oranges, are better than juice because they provide fiber and other nutrients absent from juice. (Bonus for toddlers: Oranges are fun to peel. Bummer for parents: Doing so makes a sticky mess.)

Still, the new analysis may ease some guilt around letting the juice flow. And it can enable parents to save their worries for more harmful things, of which there are plenty.

Health,, Human Development

Don’t put greasy Q-tips up your kid’s nose, and other nosebleed advice

By Laura Sanders 7:00am, March 28, 2017
Nosebleeds in children are common and usually nothing to fret about.
Human Development,, Health

Touches early in life may make a big impact on newborn babies’ brains

By Laura Sanders 12:30pm, March 22, 2017
The type and amount of touches a newborn baby gets in the first days of life may shape later responses to touch perception, a study suggests.
Human Development,, Health

See how bacterial blood infections in young kids plummeted after vaccines

By Laura Sanders 3:39pm, March 15, 2017
Rates of pneumococcal bacteremia in children plummeted by 95 percent after the introduction of vaccines against Streptococcus bacteria.
Human Development,, Health

Anesthesia for youngsters is a tricky calculation

By Laura Sanders 9:00am, March 6, 2017
Scientists, doctors and parents face uncertainty when it comes to anesthesia for babies.
Human Development,, Health

A preschooler’s bubbly personality may rub off on friends

By Laura Sanders 8:00am, February 23, 2017
Scientists caught personality shifts in preschoolers over a year by observing play.
Human Development,, Health

Birth may not be a major microbe delivery event for babies

By Laura Sanders 12:13pm, February 15, 2017
A study of mother-baby duos suggests that birth itself may not be the main event for getting microbes in and on babies.
Human Development,, Health

Little jet-setters get jet lag too

By Laura Sanders 1:00pm, February 6, 2017
Help young children fight jet lag with a few simple steps.
Health,, Human Development

A ban on screens in bedrooms may save kids’ sleep

By Laura Sanders 4:35pm, January 23, 2017
Screens are associated with worse sleep in kids, and not just because of their lights and noises.
Health

Though complex, new peanut allergy guidelines are based on science

By Meghan Rosen 1:29pm, January 13, 2017
Unlike some past recommendations, new guidelines state that introducing babies to peanut-containing foods early is generally OK, with certain caveats.
Human Development,, Health,, Neuroscience

Motherhood might actually improve memory

By Laura Sanders 11:21am, December 21, 2016
Having a baby changes all sorts of things, including a mother’s brain.
Subscribe to RSS - Growth Curve