The beief that eating sugar makes kids hyper is as close to parenting gospel as one can get. This notion is enshrined in books and film and regularly voiced on parenting blogs. It’s an idea that, on its surface, seems to make perfect sense: If sugar provides the body with energy, then kids who eat too much of it must be bouncing off the walls afterwards. You can find endless anecdotes from parents who swear that their child becoms a hyperactive tornado after binging on sugary treats.
Does sugar really make kids hyperactive?
Science frequently contradicts conventional wisdom, and the truth is that the sugar = hyperactivity idea is a thoroughly debunked myth that stubbornly refuses to die. As doctors Aaron Carrol and Rachel Vreeman state, “This myth, perhaps more than any other, is met with disbelief when we discuss it, especially among parents.” (2009, p. 113) It has been investigated over and over again, and science repeatedly fails to find any relatonship between a child’s sugar consumption and hyperactive behavior.
As Carol & Vreeman write, “there have been at least twelve trials of various diets investigating different levels of suar in what children eat. None of those studies detected any differences in behavior between the children who had eaten sugar and those who hadn’t.” Whether it’s candy, chocolate, or the natural sugars contained in fruit, children behave no differently after eating sugar than they do the rest of the time.
Are some children sensitive to sugar?
Undoubtedly some parents are thinking to themselves, +Well that may be true for most children, but my child is sensitive to sugar and he/she definitely becomes hyper after eating too much sugar. So scientists looked into this possibility as well. A study published in the +New England Journal of Medicine+ in 1994 tested “preschoolers whose parents described them as being sensitive to sugar,” notes Dr. Richard Klasco. “Neither the parent, the children nor the research staff knew which of the children were getting sugary foods” and which were receiving an artificially flavored placebo. This double-blind study found, once again, that sugar affected neither behavior nor cognitive function, even among those supposedly ‘sensitive’ kids. “One year later, an analysis that gathered data from all published studies on the subject reached the same conclusion.” (Klasco, 2020)
Why basic human physiology dooms the sugar-hyperactivity link
Basic human biology also casts doubt on this myth. While sugar can indeed provide kids with a quick boost of energy, one that might even provide a pick-me-up if their blood sugar is low and they are feeling rather sluggish, under normal circumstances it’s not going to have any effect, for a very simple reason:
The body is a fine-tuned machine, one built to regulate its energy supply. It has to be, otherwise we’d need to be eating 24/7. So even if kids do eat a lot of sugar, their body doesn’t just pour all of that energy into their system all at once. It may use some of it right away as needed to balance their blood sugar levels, but any excess is either stored in the liver and used a few hours later or converted into fat for long-term storage. (This process, in fact, is where most of the health problems linked to eating too much sugar come from.)
If this weren’t the case, then kids would similarly become hyperactive after eating a meal, especially a big one. After all, many common carbohydrates and processed foods have a glycemic index identical to table sugar. Kids don’t become hyperactive after every meal because this isn’t how the body works. So that candy bar or soda you give your kid isn’t going to spike their energy and lead to altered behavior. (The caffeine contained in many sodas, on the other hand, might.)
Why so many parents believe that sugar makes their kids hyper
If this idea is wrong, why do so many parents swear by it? The answer is that the belief in this myth causes parents to perceive their child’s behavior differently. They engage in what is known as confirmatory bias: selectively paying attention to evidence that would confirm this belief while discounting evidence that doesn’t.
In one study, children were divided into two groups. The first set of parents were told their children were receiving sugar-filled drinks. The second was told that kids were getting a placebo. The parents were then asked to monitor and grade their children’s behavior after they had consumed the beverages.
Not surprisingly, the parents who had been told to believe their kid had just consumed a lot of sugar rated them to be significantly more hyperactive. Except that none of the kids had consumed any sugar: both groups received a sugar-free placebo flavored with aspartame. The expectation that their kids were given sugar, however, altered parental perceptions of how their kids were behaving.
There are plenty of reasons to limit your child’s sugar consumption, from cavity and obesity concerns to sugar’s potential health effects. But concerns that sugar will make kids hyper isn’t one of them.
See also…
References:
Carroll, A.,Vreeman, R.C. (2009) Don’t Swallow Your Gum: Myths, Half-Truths & Outright Lies About Your Body & Health. New York: St. Martin’s Griffin
Hoover, D.W., Milich, R. (1994) “Effects of sugar ingestion expectancies on mother-child interactions.” Journal of Abnormal Child Psychology, 22(4): 501-515
Kinsbourne, M. (1994) “Sugar and the hyperactive child.” New England Journal of Medicine, 330(5): 355-56
Klasco, R. (2020, Feb. 25) “Is there a medical basis for the ‘sugar high’ that some parents claim their children get off eating sugar?” New York Times, D6
Krummel, D.A., Seligson, F.H., Guthrie, H.A. (1996) “Hyperactivity: is candy causal?” Critical Reviews in Food Science & Nutrition, 36(1-2): 31-47
Wolraich, M.L. et al. (1994) “Effects of diets high in sucrose or aspartame on the behavior and cognitive performance of children.” New England Journal of Medicine, 330(5): 301-307