Is Sugar Making Your Kids Hyperactive? Doctors Weigh In
Myths about hyperactivity and sugar in children persist, despite evidence that debunks the connection.
When my older daughter was 4, her favourite snack to bring to preschool was a chocolate chip granola bar. I tucked one into her backpack almost every day, until one afternoon I opened up her backpack and saw the granola bar still sitting there. “Are you getting sick of these?” I asked her. She wasn’t. But a new teacher had taken over the class and instituted a new rule: no sugar before lunch.
Dr Katja Rowell, M.D., a family physician and childhood feeding specialist, has a similar story: “My daughter’s preschool celebrated ‘Sugar Day’ once a year,” she recalled. “And there was so much conversation from all the adults to the kids of, ‘You’re going to be crazy! It’s crazy sugar day!’ And the kids were kind of bonkers. But there was so much anticipation of their craziness, it was like we gave them permission.”
Indeed, it has become the norm for both parents and educators to express their fear of the proverbial “sugar high” at parties, on birthdays and pretty much anytime treats are eaten, whether it’s chocolate chip granola bars or triple scoop ice cream sundaes.
“We encounter damaging messages around sugar intake from well-meaning dentists and doctors, as well as in the nutrition curriculum in early education,” said Crystal Karges, R.D.N., a registered dietitian nutritionist who focuses on mothers and families in San Diego. Yet the evidence has long shown that sugar doesn’t actually get kids high. So why does this myth persist?
“What many parents are really afraid of is the message they get from diet culture that any amount of sugar is bad for them and their kids,” said Anna Lutz, M.P.H., R.D., a dietitian in private practice in Raleigh, N.C., who writes a blog about family feeding challenges called Sunny Side Up Nutrition.
Does Sugar Cause Hyperactivity?
The theory that sugar intake could lead to what was then called “the neurotic child” was first proposed in the medical literature in 1922 and later gained popularity during the 1970s, when researchers were first trying to understand and treat attention deficit hyperactivity disorder.
“These studies were problematic because they didn’t control for so many outside factors,” Karges said. When it comes to A.D.H.D. symptoms, clinicians must consider every piece of the puzzle, she said: “We know now that the genetic make-up of a child, as well as her sleep schedule, stress level, meal structure and other environmental factors all play a role.”
Meanwhile, the sugar high concept was decisively debunked by a double-blind, controlled study published in the New England Journal of Medicine in 1994. In that experiment, researchers recruited a mix of normal preschoolers and those whose parents described them as sensitive to sugar, then randomly assigned some kids to eat sugary food and others to eat foods sweetened with aspartame. (Nobody — including parents, kids and researchers — knew which child ate what.) No behavioural or cognitive differences were detected, and as Dr Richard Klasco, M.D., reported recently in The New York Times’s “Ask Well” column, these results have been replicated in several subsequent studies.
But how to square this scientific reality with parents’ impressions of how sugar affects their children? “Our brains and bodies can feel a burst of energy after eating sugar, especially if it’s been a while since we’ve eaten and we’re feeling low on energy,” Lutz explained. “That’s because table sugar is a simple carbohydrate that breaks down quickly in our digestive tract, to reach our bloodstream.” But that quick burst doesn’t translate into hyperactivity or tantrums.
When sugar is consumed by itself, the initial energy spike can be followed by a crash as the amount of glucose in our bloodstream dips down again a little while after eating. Again, this won’t necessarily result in bad behaviour, but some kids may feel tired, hungry or moody at this stage. “Each person’s body reacts differently to food; some of us are more sensitive to blood sugar dropping than others,” Lutz said. “But these symptoms are really just an indication that it’s time to eat again.”
If kids are eating a mix of fat and protein alongside their sugar, as we find in yoghurt, for example, or my daughter’s chocolate chip granola bar, any sugar-related energy bursts and subsequent dips should be barely perceptible. Serving a glass of milk alongside a plate of cookies can even things out, Dr Rowell said, noting that many “treat foods,” like cake, offer built-in balance because they’re made with butter or another type of fat. “So if you offer milk but your child doesn’t drink it, this is not the end of the world,” Dr Rowell explained.
How you talk about food matters, too. “If you tell your child that sugar will make them act crazy, that can become a self-fulfilling prophecy,” Dr Rowell said. This can also happen if your child eats sugar only at birthday parties or other high-excitement events. If emotions are already running high about piñatas and presents, a mid-party meltdown may be inevitable, but it doesn’t mean the sugar was to blame.
Children will also pick up on your sugar anxiety if you regularly describe cookies and other treats as “bad,” or try to police how much they eat in one sitting. “The psychological effect of food restriction cannot be overstated,” Karges said. “When we restrict children’s access to sugar, they are naturally going to become more preoccupied with and drawn to these foods and overreact and have erratic behaviour when they do get them.” You can neutralise this by making sugar a regular and structured part of your family’s food life.
If you serve dessert every night with dinner, Lutz said, it’s reasonable to limit that to one child-size serving to ensure the treat doesn’t steal too much focus from other foods on the table. But it’s also important to pick times (like a regular weekend trip to the ice cream store, a cookie baking project or candy-heavy holidays) where we let children be in charge of how many treats they eat. When kids don’t feel restricted around food, it’s much easier for them to tap into how much of it they really want to eat — and their response may surprise you.
Dr Rowell encourages parents to give kids the option of saving a treat for later: “Let’s say you have dessert with dinner and you can see your child getting full. One of the most powerful things you can say is, ‘Do you want to save that brownie to have with breakfast tomorrow?’” she suggested. “Then follow through. This sends home the message that she has access to these foods and doesn’t have to eat it just because it’s there.” (Don’t stress if your child’s response is to immediately eat the brownie, though! Remember that kids are a better judge of their hunger than you.)
When you do go to birthday parties and other spaces where “sugar high” talk is likely to be rampant, avoid falling into traps like “eat three bites of pizza before you have the cupcake.” Instead, let your child choose from the food that’s offered, and if he wants seconds or thirds, say something like, “Yes, as long as there are enough for everyone to have more.”
“Kids need experiences like parties, where sugar options are readily available, in order to learn how to self-regulate the sugar intake that feels best in their bodies,” Karges said. “And they are capable of doing this if we trust them and allow them to do so.”
“Sugar Is Not The Enemy” by Virginia Sole-Smith © 2020 The New York Times Company
Virginia Sole-Smith is the author of “The Eating Instinct: Food Culture, Body Image and Guilt in America,” and co-host of the Comfort Food Podcast
This story was originally published on 17 March 2020 in NYT Parenting.