Festive Medical Myths

TOPIC: medical myths

Do you think that sugar makes kids hyperactive and late-night eating makes people fat?

You're not alone. Those are just two of many medical-related beliefs commonly held by people around the world.

But they're also FALSE, and so are many other commonly-believed health-related assertions, as discussed in the article Festive Medical Myths recently published in the British Medical Journal (BMJ), by Rachel C. Vreeman (asst prof of paediatrics) and Aaron E. Carroll (assoc prof of paediatrics), both at the Indiana University School of Medicine.

Among the medical myths Vreeman & Carroll address:
  • Sugar Causes Hyperactivity in Children? FALSE!

    According to Vreeman & Carroll,
    At least 12 double blind randomised controlled trials have examined how children react to diets containing different levels of sugar. 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. [original text contained endnote citations of relevant articles]
    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. The differences in the children’s behaviour were all in the parents’ minds. [see Hoover & Milch, 1994, referenced below]
  • Suicides Increase Over the Holidays? FALSE!

    Vreeman & Carroll point out that "While the holidays might, indeed, be a difficult time for some, there is no good scientific evidence to suggest a holiday peak in suicides. [see the Annenburg Public Policy Center references below, as well as Bridges (2004)] … Indeed, people might actually experience increased emotional and social support during holidays. In the US, rates of psychiatric visits decrease before Christmas and increase again afterwards. [see Hillard, Holland, & Ramm, 1981] … Further debunking myths about suicide, people are not more likely to commit suicide during the dark winter months. Around the world, suicides peak in warmer months and are actually lowest in the winter.

  • Poinsettias are Toxic/Poisonous? FALSE! Vreeman & Carroll explain:
    In an analysis of 849,575 plant exposures reported to the American Association of Poison Control Centers, none of the 22,793 cases involving poinsettia resulted in considerable poisoning. No one died from exposure to or ingestion of poinsettia, and most (96%) did not even require medical treatment. In 92 of the cases, children ingested substantial quantities of poinsettias, but none needed medical treatment, and toxicologists concluded that poinsettia exposures and ingestions can be treated without referral to a healthcare facility. Another study, looking at poinsettia ingestion by rats, could not find a toxic amount of poinsettia, even at amounts that would be the equivalent of 500-600 poinsettia leaves or nearly a kilogram of sap. [citations can be found in original text]

Some other beliefs Vreeman & Carroll look at and expose as groundless or outright false involve heat loss from one's head, nocturnal feasting, and curing hangovers.

Makes for entertaining and educational reading, especially when combined with their earlier paper on Medical Myths [see full citation below], in which they discuss commonly-held (but baseless) beliefs involving: drinking 8 glasses of water per day, the sleep-inducing properties of turkey, using only 10% (or some other small fraction) of one's brain, etc.

Perhaps JUST as entertaining, educational, and … sobering (?) are some of the reader responses to the original Vreeman & Carroll article (back in 2007), several of which manage (by example) to illustrate the challenges inherent in communicating scientific findings to the general public …
see e.g.
"stupid and irresponsible" by david clarke [22 December 2007],
"unbelievable and shameful!" by Mikhail Vinin [23 December 2007],

but also the heartening responses exemplified by responses such as:
"Orders of magnitude?" by Andrew J Rees [24 December 2007]


Annenberg Public Policy Center. Media continue to perpetuate myth of winter holiday-suicide link. www.annenbergpublicpolicycenter.org/Downloads/Adolescent_Risk/Suicide/myth_holiday_suicides20011204.PDF.

Annenberg Public Policy Center. Holiday-suicide link: newspapers turn the corner. www.annenbergpublicpolicycenter.org/Downloads/Releases/Release_HolidaySuicide_111907/suicidereleasenov152007final.pdf.

Annenberg Public Policy Center. The Holiday-Suicide Myth: newspapers (and TV shows) return to old ways. Report accessed Wed 12/30/2008 at http://www.annenbergpublicpolicycenter.org/Downloads/Releases/Release_HolidaySuicide/suiciderelease%202008%20with%20tables.pdf

Bridges, F. S. (2004). Rates of homicide and suicide on major national holidays. Psychol Rep, 94, 723-724.

Hillard, J. R., Holland, J. M., & Ramm, D. (1981). Christmas and psychopathology. Data from a psychiatric emergency room population. Arch Gen Psychiatry, 38, 1377-1381.

Hoover, D. W. & Milich, R. (1994). Effects of sugar ingestion expectancies on mother-child interactions. Journal of Abnormal Child Psychology, 22, 501-15.

Vreeman, R. C. & Carroll, A. E. (2007). Medical myths. BMJ, 335, 1288-1289. Full text accessed Wed 12/30/2008 at http://www.bmj.com/cgi/content/full/335/7633/1288

Vreeman, Rachel C. & Carroll, Aaron E. (2008). Festive medical myths. BMJ (British Medical Journal), 337(7684), doi: 10.1136/bmj.a2769. Full text article accessed online Wed 12/30/2008 at http://www.bmj.com/cgi/content/full/337/dec17_2/a2769.