ROBERT SIEGEL, host:
SIEGEL: Earlier this year we talked about some medical myths here, myths like shaving makes the hair grow back faster, things that your mother, or even your doctor may have told you that are just aren't true. Well, now family physician and former assistant Surgeon General Douglas Kamerow has some more myths that are tied to the holidays.
Dr. DOUGLAS KAMEROW (Family Physician, Former Assistant Surgeon General): Once again, Indiana University doctors Rachel Vreeman and Aaron Carroll have debunked a group of health-related myths in an article in the medical journal, BMJ. As we approach the end of the year and its attendant celebrations, bear these scientific findings in mind.
First of all, you don't have to worry about the poinsettias around your house if you have kids or pets. Despite long-standing beliefs to the contrary, poinsettia leaves and flowers are not poisonous. Both toxicity studies in rats and reviews of Poison Control Center data about human ingestion have failed to find any toxic level of poinsettia.
Here's one that will make your kids happy: Eating sugar and sweets does not make children hyperactive. Although countless parents will swear it's not true, at least a dozen carefully controlled studies have failed to find any effect of dietary sugar on children's behavior. And some of this research was even done on hyperactive kids who were thought to be at greater risk for this reaction. It turns out that at least part of the problem is parental expectations. This was confirmed by a study that had parents score their children's behavior after they consumed what the parents thought was a sugary drink. Even when the drink contained no sugar, the parents rated their kids' behavior as hyperactive. So, bring on the sugarplums.
On a more serious note, the common wisdom that suicides are more frequent during the winter holiday season is also false. Studies done around the world have failed to find a spike in suicide rates, either during the holidays, or during the cold, dark winter months. Suicide levels peak at different times in different countries among people of different ages, but there is no consistent pattern.
Speaking of cold weather, how many times have you heard that you lose most of your body heat through your head? My mother certainly told me that, and even the U.S. Army Survival Manual tells us that soldiers lose 40 to 45 percent of body heat through their heads. But recent studies have debunked this old soldier's tale. Any uncovered part of the body loses heat and will drop the core body temperature proportionately. If you walk outside in winter with a hat on, but wearing shorts, you're gonna be cold.
Finally, for New Year's Eve, what's your favorite nostrum to prevent or treat a hangover? Bananas? Burnt toast? Black coffee? Raw eggs? Surprisingly few scientific studies have been done of hangover medicines and, unfortunately, no scientific evidence supports any cure for drinking too much. Some studies in rats show promising potential treatments, but nothing is ready for prime time yet. Bottom line? Drink alcohol in moderation if you don't want a hangover. And have a happy, healthy new year.
SIEGEL: Family physician, Douglas Kamerow, is a chief scientist at the research organization RTI International.
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