Does Sugar Cause Your Kids to be Hyperactive?

Dad is enjoying a night out with the kids. Dad, Billy, and Joey scarf down some hamburgers and french fries, enjoy a kick-butt action movie (don’t tell mom) and, for the piece de resistance, they stop off at the ice cream parlor for some loaded hot fudge sundaes. Dad doesn’t know it, but he’s in trouble.

When the fun-loving trio return home, Dad shuffles off to the kitchen to raid the refrigerator (is this guy ever full?), while Billy and Joey run to the family room. Mom notices the tell-tale residue of sticky hot fudge on the corners of their mouths. Oh, boy, I’m in for it, she thinks. Billy and Joey proceed to run around like a couple of little wild men, while mom tries to corral them and stop them from destroying the place.

Poor mom. She graciously suggested this boys-night-out and has been home trying to deal with the ever-accumulating pile of dirty laundry. Now, she’s dealing with a couple of sugared-up boys. The idea was to tire them out, not pep them up, she thinks.

Mom marches off to the kitchen, where Dad is staring into the open fridge as if the contents will change if he just looks at them long enough. Mom closes the fridge door with a slam. “So, you thought it was a good idea to feed two little boys sugar right before bedtime? You know that sugar makes them hyper! I’ll never get them to bed!”

Dad grins sheepishly. “But they had such a good time,” he replies.

According to the Evidence, Sugar Does Not Cause Hyperactivity In Children

Dad has a secret. He doesn’t really believe that sugar makes kids hyperactive. You see, when he’s not staring into the fridge he’s been reading sites like Culinary Lore and he’s come across an article that clued him into an interesting fact: There is no evidence that sugar makes kids hyperactive. Now, I’m not saying Dad is smarter than mom. But he is smart enough to know he won’t win this particular argument.

But the same thing that happened to Billy and Joey has been noticed by parents everywhere, especially after such events as birthday parties where kids fill up on cake and ice cream and even crack open the occasional pinata. You can hardly attend such a party without at least one parent commenting on how hyper the kids are going to be after “eating all that sugar.”

Most People Believe that Sugar Makes Children Hyper

It’s an obvious enough causal inference. Kids eat a bunch of sugary foods and then they “bounce off the walls” as the expression goes. Sugar goes straight to the blood and causes a sudden and quick burst of energy and the children have to work off all the excess. Have you ever asked yourself why this doesn’t happen to you? Personally, if I eat a giant piece of rich chocolate cake the last thing I feel is energized. Yet, according to surveys, most people, including most parents, college students, and even many doctors believe that too much sugar causes kids to be hyperactive.

This belief is portrayed and greatly exaggerated in countless movies and television shows, where children given sugar don’t just act energized but go absolutely bananas. There is also the “sugar meltdown” when too much sugar, so we believe causing a crying fit or a tantrum.

My Kid is ‘Sugar Sensitive’

Since some parents, of course, do not notice such an effect in their children, some parents who have noticed an effect (or believe they have) label their children as “sugar sensitive.” But, well-designed placebo-controlled studies overwhelmingly show no association between sugar intake and hyperactivity. 1

Why Do Parents Believe It?

We have to ask, then, what is at work here? If there is no consistent relationship between excessive sugar intake and the subsequent “bouncing off the walls” effect that parents believe they have witnessed, what is really happening? If it’s not the sugar, what is it?

One study was conducted to try to tease out the mechanism at work. In this study, 35 five to seven-year-old boys with their parents on hand were supposedly split into two random groups: One which received a sugar drink and another which received a drink sweetened with artificial sweetener. In other words, half the mothers believed that their children were given a huge dose of sugar, and the other half believed their children were given a placebo. All these boys’ mothers had reported their sons to be “sugar sensitive.”

In reality, both groups received a drink which was sweetened with aspartame. None of the kids got any sugar! After the beverages were consumed, the mother and their children participated in a structured play task. In the questionnaire that followed, the mothers who believed their kids had drunk the sugar-sweetened drink reported their children to be much more “hyperactive” than the mothers in the no-sugar group. These moms also were more restrictive and controlling of their children during the play task. 2

This study was clever in that it broke the rules to see if just such an expectancy effect would occur. An expectancy effect occurs when the subject of an experiment expects a certain result and therefore either reports this result or even unconsciously affects the outcome of the experiment. Normally, studies are double-blinded to eliminate such an effect. If both of the groups had been “blinded” then the mothers would not have known whether their children received the sugar or the placebo beverage. Here, the mothers were told what they received while, in reality, both groups received a placebo. Therefore, it could not be anything but the expectation of the mothers which caused the reports to differ.

So, the idea is that parents believe that sugar affects their children’s activity level and ability to sit steal, behave, and concentrate and they, therefore, interpret their children’s behavior in this light. See, if you know Billy and Joey, you know that they often act like little wild-men, especially after they’ve had a fun day. Mom knows this, but it doesn’t stop her from being convinced, after spying that hot-fudge gunk, that they are about to go ballistic. As well, this causes her to try to curtail their behavior a bit more than usual. Could this also affect their behavior?

And, let’s be real. Billy and Joey had a great night! They positively partied down. They are still excited, full of the rush of an afternoon well-spent.

Isn’t This a Harmless Myth?

So, what? you ask. Does it really matter very much if parents restrict their children’s sugar intake because they falsely believe that too much sugar makes them hyperactive? No. For the most part, it doesn’t. Controlling your children’s intake of simple sugars is not a bad idea, even if it makes them miserable.

But what we label as “our kids being hyper” is, in colloquial terms, vague and imprecise. Heck, our mood and energy level will help dictate what we call “hyper” in our children. The problem is that this myth was very well established by the time people became commonly aware of what is now called ADHD, or Attention Deficit Hyperactivity Disorder. It may have been inevitable that this widely accepted connection between sugar and hyperactivity was transferred to ADHD, making some parents believe that sugar either caused their kid’s ADHD or greatly aggravated it. Billy and Joey’s mom knows they will tire themselves out. It’s an acute problem, not a chronic one. She doesn’t need to deny them candy bars for the rest of their lives. She just isn’t going to fill them up on hot fudge sundaes at the end of the day.

For parents of children with ADHD who believe that sugar affects their children’s ability to, for instance, learn in school, may not only deny them the occasional candy bar but attempt to cure the problem by trying to eliminate all sugar from their diet. Such sugar elimination diets may sometimes be a simple distraction from the sort of treatment that will have a positive impact on the child. The kind of treatment backed by evidence. Worse, such elimination diets may go way too far and attempt to eliminate any and all sugar from the diet. This is especially problematic when coupled with the fraught beliefs that sugar is addictive or that sugar causes diabetes. When such diets are attempted with the advice of a qualified dietician, too many healthy foods may be eliminated. 1

This is not to mention that such restrictions and undue attention to diet may have a very negative effect on a child. No matter what, we can be fairly certain that avoiding sugar will not make the little Billies and Joeys of the world stop being little wild-men.