By Helen Branswell, Llpmedical Reporter, The Canadian Press
TORONTO - Are you one of those who knows for a fact that poinsettias are poisonous and that candy canes and sugar plums will have the kids dancing on their hyperactive heads this Christmas?
You wear hats in winter because you know most of your body heat is lost through your head? You avoid eating at night because you know it will make you fat? You are certain that suicides peak over the holidays and that somewhere there exists a nostrum that will cure the hangover that will threaten to crush your head New Year's Day?
Ho-ho-hold on there!
All those commonly held beliefs are untrue, say myth busters extraordinaire Dr. Rachel Vreeman and Dr. Aaron Carroll in a paper published Thursday in the Christmas issue of the British Medical Journal.
The duo, co-authors of the pending "Don't Swallow Your Gum: Myths, Half-Truths and Outright Lies About Your Body and Health," have taken another run at testing the truthiness of commonly held medical beliefs for the journal's light-hearted holiday issue.
Last year they made waves by dispelling the notions that we should all drink eight glasses of water a day, we only use one-tenth of our brain and our hair and fingernails continue to grow after our deaths, among other accepted, if erroneous, "facts."
The feedback - some of it quite heated, judging by the journal's website - prompted Myth Busters 2.0, this time with a seasonal theme.
Carroll and Vreeman admitted that when they embarked on this year's collection of accepted wisdom they expected to find some of the items were actually true.
"I have three kids... I was sure that sugar made kids hyperactive," says Carroll, director of Indiana University's centre for health policy and professionalism research.
"It just seemed like common sense.... So that was shocking to me and I still think that most of my friends probably don't believe me."
In addition to being pediatricians and pediatrics professors in the university's school of medicine, the pair teach medical students how to critically assess scientific literature. And it was that work that inspired this project.
"There are a lot of things that we take for granted that if we actually think about critically and look into, it turns out we're not quite correct," Carroll says.
So they mined the scientific literature, looking for proof for or against their list of medical truths.
First up was sugar and kids. Everybody believes this one is true, despite the fact that there are reams of randomized controlled trials - OK, at least 12 - that show sugar consumption doesn't make children behave differently, says Vreeman.
In fact, kids' sugar consumption seems to have a bigger impact on parents than on their kids. At least one study has shown that parents who think their kids have eaten sweets rate their behaviour as more hyperactive, whether the kids actually ate sugar or not.
Dr. Donald Redelmeier, a Toronto epidemiologist, says parents aren't completely off the mark - they're just blaming the wrong thing for their children's frenetic energy.
"I think it's a product of the circumstances, i.e. the types of settings where sugar is often served are like birthday parties and festivals," says Redelmeier, who is with the Institute for Clinical Evaluative Sciences and who was not involved in this study.
"And so that what's going on here is that under those circumstances, yeah, children are often running around and yelling and screaming, having a good time. But it's the fundamental attribution error. It's not so much a reflection of the sugar that they're eating but just other aspects of the circumstances."
]
As for poinsettias, a study that looked at data from 22,793 calls about poinsettia ingestion made to U.S. poison control centres found no deaths and no one who really even needed medical care.
"There's no evidence that poinsettias ... are toxic, that people die from them," says Vreeman, but she adds that "they taste horrible" and they should be left off the holiday menu.
Eating at night is like eating in the daytime - a calorie is a calorie, whenever it is consumed. Though people who eat more at night may be eating more all day long.
The list of hangover cures is long and imaginative, but there is no evidence any of them actually work, Vreeman and Carroll say.
And as for losing body heat through the head, they say the issue there is that any part of the body that is uncovered will lose heat at the same rate - it's just most people don't expose their navels or legs during the winter. Bare heads, however, are commonly seen.
"There's nothing special about the head compared to another part of the body of basically the same surface area," Vreeman says.
"Whatever's uncovered is going to lose heat. So if you're cold and your head is the only thing uncovered, sure, you should put a hat on."
As for the idea that suicide rates rise during the holidays because of loneliness, the stress of family dysfunction or depression over the bleakness of the winter months, Carroll and Vreeman say that the multitudes of studies that looked at this issue don't support the claim.
"There's just no peak associated with the holidays," Vreeman says. "And in fact suicides are actually more common during the warm and sunny parts of the year, wherever people tend to be - which I think was a real surprise to us."
Redelmeier reserved judgment on that one, however, saying he thinks the pair didn't analyze all of the studies that exist on this topic and "the jury's still out on that one."
His reluctance to accept Vreeman and Carroll's assertion on that issue nicely illustrates how hard it is to dislodge ideas like these that have become accepted parts of the collected societal knowledge.
"These are widely and strongly held beliefs that are not quickly extinguished," Redelmeier says. "You know, many superstitions in our society are just awfully hard to eradicate."
TORONTO - Are you one of those who knows for a fact that poinsettias are poisonous and that candy canes and sugar plums will have the kids dancing on their hyperactive heads this Christmas?
You wear hats in winter because you know most of your body heat is lost through your head? You avoid eating at night because you know it will make you fat? You are certain that suicides peak over the holidays and that somewhere there exists a nostrum that will cure the hangover that will threaten to crush your head New Year's Day?
Ho-ho-hold on there!
All those commonly held beliefs are untrue, say myth busters extraordinaire Dr. Rachel Vreeman and Dr. Aaron Carroll in a paper published Thursday in the Christmas issue of the British Medical Journal.
The duo, co-authors of the pending "Don't Swallow Your Gum: Myths, Half-Truths and Outright Lies About Your Body and Health," have taken another run at testing the truthiness of commonly held medical beliefs for the journal's light-hearted holiday issue.
Last year they made waves by dispelling the notions that we should all drink eight glasses of water a day, we only use one-tenth of our brain and our hair and fingernails continue to grow after our deaths, among other accepted, if erroneous, "facts."
The feedback - some of it quite heated, judging by the journal's website - prompted Myth Busters 2.0, this time with a seasonal theme.
Carroll and Vreeman admitted that when they embarked on this year's collection of accepted wisdom they expected to find some of the items were actually true.
"I have three kids... I was sure that sugar made kids hyperactive," says Carroll, director of Indiana University's centre for health policy and professionalism research.
"It just seemed like common sense.... So that was shocking to me and I still think that most of my friends probably don't believe me."
In addition to being pediatricians and pediatrics professors in the university's school of medicine, the pair teach medical students how to critically assess scientific literature. And it was that work that inspired this project.
"There are a lot of things that we take for granted that if we actually think about critically and look into, it turns out we're not quite correct," Carroll says.
So they mined the scientific literature, looking for proof for or against their list of medical truths.
First up was sugar and kids. Everybody believes this one is true, despite the fact that there are reams of randomized controlled trials - OK, at least 12 - that show sugar consumption doesn't make children behave differently, says Vreeman.
In fact, kids' sugar consumption seems to have a bigger impact on parents than on their kids. At least one study has shown that parents who think their kids have eaten sweets rate their behaviour as more hyperactive, whether the kids actually ate sugar or not.
Dr. Donald Redelmeier, a Toronto epidemiologist, says parents aren't completely off the mark - they're just blaming the wrong thing for their children's frenetic energy.
"I think it's a product of the circumstances, i.e. the types of settings where sugar is often served are like birthday parties and festivals," says Redelmeier, who is with the Institute for Clinical Evaluative Sciences and who was not involved in this study.
"And so that what's going on here is that under those circumstances, yeah, children are often running around and yelling and screaming, having a good time. But it's the fundamental attribution error. It's not so much a reflection of the sugar that they're eating but just other aspects of the circumstances."
]
As for poinsettias, a study that looked at data from 22,793 calls about poinsettia ingestion made to U.S. poison control centres found no deaths and no one who really even needed medical care.
"There's no evidence that poinsettias ... are toxic, that people die from them," says Vreeman, but she adds that "they taste horrible" and they should be left off the holiday menu.
Eating at night is like eating in the daytime - a calorie is a calorie, whenever it is consumed. Though people who eat more at night may be eating more all day long.
The list of hangover cures is long and imaginative, but there is no evidence any of them actually work, Vreeman and Carroll say.
And as for losing body heat through the head, they say the issue there is that any part of the body that is uncovered will lose heat at the same rate - it's just most people don't expose their navels or legs during the winter. Bare heads, however, are commonly seen.
"There's nothing special about the head compared to another part of the body of basically the same surface area," Vreeman says.
"Whatever's uncovered is going to lose heat. So if you're cold and your head is the only thing uncovered, sure, you should put a hat on."
As for the idea that suicide rates rise during the holidays because of loneliness, the stress of family dysfunction or depression over the bleakness of the winter months, Carroll and Vreeman say that the multitudes of studies that looked at this issue don't support the claim.
"There's just no peak associated with the holidays," Vreeman says. "And in fact suicides are actually more common during the warm and sunny parts of the year, wherever people tend to be - which I think was a real surprise to us."
Redelmeier reserved judgment on that one, however, saying he thinks the pair didn't analyze all of the studies that exist on this topic and "the jury's still out on that one."
His reluctance to accept Vreeman and Carroll's assertion on that issue nicely illustrates how hard it is to dislodge ideas like these that have become accepted parts of the collected societal knowledge.
"These are widely and strongly held beliefs that are not quickly extinguished," Redelmeier says. "You know, many superstitions in our society are just awfully hard to eradicate."
