Intended for healthcare professionals

Feature Christmas 2008: Seasonal Fayre

Festive medical myths

BMJ 2008; 337 doi: (Published 18 December 2008) Cite this as: BMJ 2008;337:a2769
  1. Rachel C Vreeman, assistant professor of paediatrics1, faculty investigator 2,
  2. Aaron E Carroll, associate professor of paediatrics1, director2
  1. 1Children’s Health Services Research, Indiana University School of Medicine, Indianapolis, IN, USA
  2. 2Center for Health Policy and Professionalism Research, Indiana University School of Medicine, Indianapolis, IN, USA
  1. Correspondence to: R C Vreeman rvreeman{at}

More medical myths hit the dust, thanks to Rachel C Vreeman and Aaron E Carroll

In the pursuit of scientific truth, even widely held medical beliefs require examination or re-examination. Both physicians and non-physicians sometimes believe things about our bodies that just are not true. As a reminder of the need to apply scientific investigation to conventional wisdom, we previously discussed the evidence disputing seven commonly held medical myths.1 The holiday season presents a further opportunity to probe medical beliefs recounted during this time of the year.

We generated a list of common medical or health beliefs related to the holidays and winter season and searched Medline for scientific evidence to support or refute these beliefs. If we couldn’t find any evidence in the medical literature, we searched the internet using Google.

Sugar causes hyperactivity in children

While sugarplums may dance in children’s heads, visions of holiday sweets terrorise parents with anticipation of hyperactive behaviour. Regardless of what parents might believe, however, sugar is not to blame for out of control little ones. At least 12 double blind randomised controlled trials have examined how children react to diets containing different levels of sugar.2 None of these studies, not even studies looking specifically at children with attention-deficit/hyperactivity disorder, could detect any differences in behaviour between the children who had sugar and those who did not.3 This includes sugar from sweets, chocolate, and natural sources. Even in studies of those who were considered “sensitive” to sugar, children did not behave differently after eating sugar full or sugar-free diets.3

Scientists have even studied how parents react to the sugar myth. When parents think their children have been given a drink containing sugar (even if it is really sugar-free), they rate their children’s behaviour as more hyperactive.4 The differences in the children’s behaviour were …

View Full Text

Log in

Log in through your institution


* For online subscription