• Healthcare Triage: Sugar doesn’t make kids hyper

    Healthcare Triage #3 is up. What’s Healthcare Triage? Glad you asked:

    Healthcare Triage is a series about healthcare. Dr. Aaron Carroll will explain healthcare policy, medical research, and answer a lot of other questions you may have about medicine, health, and healthcare. Not only that, the videos are going to be pretty fun. John Green will stop in regularly to have his hypochondria soothed by Aaron’s clear and engaging explanations. Healthcare Triage is made by the people who make Crash Course, mental_floss video, and The Art Assignment.

    This one is about randomized controlled trials:

    Do you think that sugar makes kids hyper? Well, you’re wrong. Yes, WRONG. How do we know? Randomized controlled trials.

    RCTs are pretty much the most robust study design there is, and also the only way to prove causality. This week’s episode of Healthcare Triage explains how randomized controlled trials work, and why they are superior to other types of studies. It also explains how they’ve been used to prove, without a doubt, that sugar doesn’t make kids hyper. Don’t believe it? Watch the video and argue with us in the comments below if you’re still not convinced.

    Please watch and share! We need support in terms of subscribers and viewers to keep this going!


    • So why do you not have the studies listed at the end of your video? (preferably in an open access form) Surely, you do not want people to change their viewpoints just on the basis of your arguments without access to the details of the studies.

    • I never thought sugar did that.

    • It seems to me that the most likely truth is that overtired kids can get hyper and they seek sugar for energy, which keeps them going until bedtime. Maybe without the sugar, they’d have conked out and the parents would have associated the hyper phase with tiredness, not sugar.

      Or maybe hyper kids have high-energy pester power which tends to get rewarded with cookies by parents who see the high-energy as hungry kid really wants cookie, not hyper kid would be employing as much energy begging for a non-edible treat if he knew something new and interesting was in a jar in the kitchen.

      It wouldn’t be the first time common wisdom says A causes B when it’s really the other way around.

    • I have tried to convince people of this but to no avail.

    • Excellent

    • Considering that there are no randomize controlled trial on trans fat and that people, including scientists have biases that tend toward finding results and especially against fat, I think that a ban is probably not justified. The Nurses study used surveys which is not so great.

    • I don’t know that I exactly agree with your conclusion, but correct me if I am wrong. What a double blinded, randomized, placebo controlled trial will tell you is whether in the aggregate one “treatment” causes a statistically significant difference in outcomes compared to no treatment. If the results of the trial are that in the aggregate the treatment shows no difference compared to no treatment, this does not mean that it had no effect on anyone. There are most certainly members of the treatment group who saw some effect of the treatment. That is to say there very well maybe some kids who have a hypersensitivity to sugar, but there are just as many who likely don’t.

      So your conclusion that sugar does not cause hyperactivity in kids is a bit misleading. What you really should say is that sugar is no more likely to cause hyperactivity than no sugar.

      • Great point from a scientific mind! Thanks for sharing!!

      • “That is to say there very well maybe some kids who have a hypersensitivity to sugar, but there are just as many who likely don’t.”

        No. This doesn’t work.

        If some kids were sensitive to sugar, and others were not, we would still be able to see the effects of sugar. (To the extent that sugar sensitivity was rare, we would need a larger sample size to detect it: but by the same token, our failure to detect it would imply that sugar sensitivity was [at least] rare.)

        But if sugar-sensitivity is common enough to be non-trivially represented in our sample, then we will fail to observe it only if sugar makes some calm kids hyper while making an identical number of otherwise hyper kids calm.

        So the options are:
        1. Sugar doesn’t make kids observably hyper.
        2. Sugar makes some kids hyper, but this effect is very rare: the proportion of kids affected is too tiny to be detected without a larger study.
        3. Sugar makes some kids hyper who would otherwise be calm, makes some kids calm who would otherwise be hyper, and does this in perfectly calibrated proportion so as to hide its own effects from detection.

        Note that all three options contradict the conventional wisdom that sugar routinely makes kids hyper, not placid. And obviously I think options 1 and 2 are more plausible than option 3.

    • Your explanations for why people hold this belief about sugar and hyperactivity are not very convincing. I suspect parents are seeing something however imperfectly which will be confirmed in 2025 in a study. At that point someone will make a video with the same smugness and condescension telling people “remember when dad said sugar doesn’t cause hyperactivity, well…..”

      • No, if they were seeing something associated with sugar, it would show up in studies that ask them to assess what they see with and without sugar. I’m totally comfortable in my assessment. That’s the beauty of science.

    • One problem with the sugar and sugar free candy trial design is the assumption that sugar free candy is metabolically neutral. In fact, it is not. There are “sweet receptors” in many places in the body, including in the brain, and they are activated by non-sugar sweeteners as potently as by sugar. So this particular study design is non-ideal. A better approach would be to separate in time and space the administration of sugar (or not giving sugar) from an independent behavioral evaluation by observers blinded to whether the children received sugar or not.