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Why does sugar make kids hyper?  Is it really a “sugar high”? – KT, Stratford, CT

The belief that sugar makes kids “hyper” has been around for many, many years. Everyone knows this is true, right? It’s been a staple of family sitcoms for generations, after all. Except it’s completely false.

Not only is the idea “sugar makes kids hyper” not true, we’ve known that it isn’t true for a long time. This was the research focus of Dr. Mark Wolraich in the early 1990s and he clearly demonstrated that eating sugar does not lead to hyperactivity in children – neither right after eating a high-sugar treat nor when eating a high-sugar diet over time. Dr. Wolraich and his group even took their investigation a step further, asking why parents always associated high sugar intake with hyperactivity. The answer: observation bias.

Mothers who were told their children had eaten a large amount of sugar described their children as “hyper” even when they hadn’t actually been given any sugar by the researchers, and visa-versa. The mothers even behaved differently toward children they believed had eaten sugar regardless of whether they actually had. Parents had been hearing that sugar causes hyperactivity for so long, it colored their opinions of their children’s behavior.

This actually makes perfect biological sense when you think about it: blood sugar is very tightly controlled in most people, and when a healthy person eats a lot of sugar, that sugar is quickly turned to fat rather than remaining in the blood. It is true that diabetics with low blood sugar are often fatigued and lethargic, but what happens with diabetics who experience hyperglycemia (very high blood sugar levels)? As it turns out, hyperactivity and increased energy are not among the symptoms: instead, fatigue is a common symptom. Sugar simply is not a stimulant.

So the whole thing is a myth – sugar causing hyperactivity and “sugar highs” – they have been scientifically proven false. You may think your child has more energy after that non-diet soda, but it’s likely just your perception as a biased observer (or maybe the caffeine in that soda). You can’t be trusted. What I find most fascinating about this myth is that it’s been debunked all over the Internet: go ahead and google it! (Or Bing it, if you’re one of those people) You’ll find plenty of experts referencing Dr. Wolraich’s work and de-bunking the myth – like this, and this, and this. What you won’t find is many people supporting this outdated theory. It’s interesting that a clear, fact-based answer to this question has been freely available as long as the internet has been around, and yet the myth persists.

Now, this certainly isn’t a licence to give your kids all the sugary treats they want.  High sugar diets are most certainly linked to obesity, diabetes, and of course cavities.  It’s probably still a good idea to keep your kid away from excessive sugar.  Just don’t think it’s going to help with their behavior.