Pediatric professors Rachel C. Vreeman and Aaron E. Carroll (website of both), from the Indiana University School of Medicine (Indianapolis, U.S.A.) state in the abstract to their paper, “In the pursuit of scientific truth, even widely held medical beliefs require examination or re-examination.”
They add, “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."
"The holiday season presents a further opportunity to probe medical beliefs recounted during this time of the year.”
The BMJ article states, "More medical myths hit the dust, thanks to Rachel C. Vreeman and Arron E. Carrol."
Vreeman and Carrol researched medical literature databases and other medical literature, and when needed, conducted Google Internet searches, to find evidence that supported or denied these beliefs.
Their six common medical beliefs include toxic poinsettias, high holiday suicide rates, curable hangovers, sugar-induced hyperactive children, head-heat-loss in humans, and nocturnal eating makes one fat.
Dr. Vreeman states, "We really don't know why some myths become so embedded.” [Washington Post: “Toxic Poinsettias? Hangover Cures? It May Be All Fiction”]
Page two continues with some of the myths.
Dr. Carroll adds, "Sometimes you hear these myths from people you consider to be experts. And, often, there's a kernel of truth in some of these myths. For example, sugar gives us energy, so some people might leap to the conclusion that too much sugar gives you too much energy." [Washington Post]
“With flowers and leaves of red, green, and white, poinsettias are widely used in holiday decorations. Even though public health officials have reported that poinsettias are safe, many continue to believe this is a poisonous plant.”
For instance, they found analysis that had been performed on 849,575 plant exposures, as reported to the American Association of Poison Control Centers. Carroll and Vreeman discovered that none of the 22,793 cases involving poinsettia resulted in “considerable poisoning.” In addition, nobody died from such exposure or ingestion of poinsettias, and in 96% of the cases the person did not even require medical treatment.
2. Suicides rates increase over the holidays
“Holidays can bring out the worst in us. The combined stresses of family dysfunction, exacerbations in loneliness, and more depression over the cold dark winter months are commonly thought to increase the number of suicides. While the holidays might, indeed, be a difficult time for some, there is no good scientific evidence to suggest a holiday peak in suicides.”
“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. In Finland, suicides peak in autumn and are lowest in the winter. In a 30 year study of suicides in Hungary, researchers again found the highest rates of suicides in the summer and the lowest in the winter. Studies of suicide rates from India also show peaks in April and May. Studies from the US reflect this pattern, with lower rates in November and December than in typically warmer months.”
The researchers admit that suicides do happen during holidays such as Christmas, Easter, Thanksgiving, and others. However, the rate of suicide is not increased during these holiday times.
Dr. Collins states, "There are such high expectations around the holidays. Holiday anxiety and depression are very common, so a better question might be whether or not people are more unhappy during the holidays." [Washington Post]
Page three continues with more myths.
3. Hat-less heads lose more heat than other parts of the body
“This myth probably originated with an old military study in which scientists put subjects in arctic survival suits (but no hats) and measured their heat loss in extremely cold temperatures. Because it was the only part of the subjects’ bodies that was exposed to the cold, they lost the most heat through their heads. Experts say, however, that had this experiment been performed with subjects wearing only swimsuits, they would not have lost more than 10% of their body heat through their heads."
"A more recent study confirms that there is nothing special about the head and heat loss. Any uncovered part of the body loses heat and will reduce the core body temperature proportionally. So, if it is cold outside, you should protect your body. But whether you want to keep your head covered or not is up to you.”
Dr. Vreeman adds, "We often hear parents say that as long as their kids are wearing a hat, they feel that they're sufficiently dressed. Of course they should bundle up for protection from the cold, but they should be equally concerned about gloves and boots as well." [CNN Health: “Relax -- Your holiday health concerns may just be myths”]
4. Eating late at night makes you fat
“Holiday feasts and festivities present us with many culinary options. A common suggestion to avoid unwanted weight gain is to avoid eating at night, and at first glance, some scientific studies seem to support this. In a study of 83 obese and 94 non-obese women in Sweden, the obese women reported eating more meals, and their meals were shifted to the afternoon, evening, or night. But just because obesity and eating more meals at night are associated, it does not mean that one causes the other.”
The conclusion of this study was that the Swedish women just ate more calories than the calories they burned. These fat women were fat because they ate a lot throughout the night and night, and not just at night. Taking in more calories, according to the researchers,“makes you gain weight regardless of when calories are consumed.”
And, page four talks about the rest of the myths.
5. Curable hangovers
"No scientific evidence, however, supports any cure or effective prevention for alcohol hangovers."
“A hangover is caused by excess alcohol consumption. Thus, the most effective way to avoid a hangover is to consume alcohol only in moderation or not at all.”
6. Sugar-caused 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.”
They located 12 double-blind, randomized, controlled trials that investigated the effect of excess sugar intake on children. One of the trials none found any evidence that sugar causes hyperactivity in children.
In fact, the researchers state that in one study, parents were told that their children had been given sugar when, in fact, they had not been given sugar. The parents thought that their children’s behavior was more hyperactive when they thought that the kids had been given sugar (but really hadn’t) versus when they thought their children had not been given sugar (and in fact they hadn’t).
The researchers stated, “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.”
Dr. Collins added, "A lot of occasions when kids are exposed to sugar are when they are most likely to be super excited, running around, and acting out. They get more ice cream and candy often at times when they are at parties, getting presents, and seeing friends, and these factors all contribute." [CNN Health]
Page five concludes.
Their conclusions to all of these six medical myths/beliefs: “Examining common medical myths reminds us to be aware of when evidence supports our advice, and when we operate based on unexamined beliefs."
"Only by investigation, discussion, and debate can we reveal the existence of such myths and move the field of medicine forward.”
Dr. Carroll also concludes with this bit of advice: "With the Internet today, it's easier to find good information but it's also just as easy to find bad [information].
He also adds, "Doctors spend a lot of time simply doing things they've been told to do or things they've learned in the past." [CNN Health]
In other words, even though your grandmother, your family doctor, and the local expert-on-everything tells you something is a fact ... they may be wrong.
Additional information is found in the ScienceDaily.com article "Medical Myths For The Holiday Season: True, False Or Unproven?"