Being healthy means having accurate information. Many times it’s hard to separate truth from fiction on the complex issues of health, medicine, diet, and exercise, and we’re not going to pretend that we can clear everything up in an article. However, LiveScience.com can bust several health myths for you, including some that will keep you happier during the holidays. All these myths come from articles in the British Medical Journal.
Myth: Sugar makes kids hyperactive.
“There have been more studies on this than on many drugs,” said article author Dr. Aaron Carroll of the Indiana University School of Medicine, “all of which show there is no link between sugar and hyperactivity.” Even if the kids are “sugar sensitive” or have attention-deficit disorder, he continued, sweets do not change their behavior.
Parents may think their kids become more chaotic after candy and other treats but “it is in their heads,” said primary author Dr. Rachel Vreeman, also of the Indiana University School of Medicine. She pointed to a study that told parents their kid was slurping a sugar-loaded beverage, when the drink instead was essentially water. The parents reported the child going bonkers when objective observers thought otherwise, she said.
Myth: Suicides increase over the holidays.
The weather is woeful, the relatives are rude and melancholy moods abound. “But contrary to what many of us think, suicides are actually more common, around the world, during times of year that are warmer and sunnier,” Vreeman said. The article also cites a 35-year study conducted in the United States showing that holidays – including Christmas, the Fourth of July and birthdays – are not preferred times to take one’s life.
Myth: Poinsettias are toxic.
Shooing the dog or child away from the perilous plant of holiday cheer? Let the hollering subside. The American Association of Poison Control Centers has a record of 22,793 cases of human poinsettia ingestion and zero resulted in significant poisoning. Ninety-six percent of the poinsettia-eaters didn’t even need to see a doctor, Vreeman said. And rats that gobbled several hundred grams of the pureed flower, the equivalent of a human eating 500-600 poinsettia leaves, did just fine. Still, it’s best to call the poison control center when any non-food plant is eaten, she said.
Myth: You lose most of your body heat through your head.
Your mother said it. Every hat salesman touts it. Even the U.S. Army Field Manual claims “40 to 45 percent of body heat” is lost through the head, the researchers write in this week’s article, but it is simply not true. Body heat leaves from any skin surface in proportion to the area exposed, said Vreeman. As for people who claim a hat renders shorts acceptable in cold weather? “Those people are being very, very foolish,” Carroll said. “There is nothing special about the head.”
Myth: Eating at night makes you fat.
While eating late at night has been associated with obesity, midnight munching does not cause obesity. “You shouldn’t be afraid to have that midnight snack anymore than a mid-day or mid-morning snack,” Carroll said. The article, citing several studies, suggests that Santa’s jolly belly is the result of too many calories overall, not just the holiday treats laid out for him in the evening.
Myth: We use only 10 percent of our brains.
Fact: Physicians and comedians alike, including Jerry Seinfeld, love to cite this one. It’s sometimes erroneously credited to Albert Einstein. But MRI scans, PET scans and other imaging studies show no dormant areas of the brain, and even viewing individual neurons or cells reveals no inactive areas, the new paper points out. Metabolic studies of how brain cells process chemicals show no nonfunctioning areas. The myth probably originated with self-improvement hucksters in the early 1900s who wanted to convince people that they had yet not reached their full potential, Carroll figures. It also doesn’t jibe with the fact that our other organs run at full tilt.
Myth: You should drink at least eight glasses of water a day.
Fact: “There is no medical evidence to suggest that you need that much water,” said Dr. Rachel Vreeman, a pediatrics research fellow at the university and co-author of the journal article. Vreeman thinks this myth can be traced back to a 1945 recommendation from the Nutrition Council that a person consume the equivalent of 8 glasses (64 ounces) of fluid a day. Over the years, “fluid” turned to water. But fruits and vegetables, plus coffee and other liquids, count.
Myth: Fingernails and hair grow after death.
Fact: Most physicians queried on this one initially thought it was true. Upon further reflection, they realized it’s impossible. Here’s what happens: “As the body’s skin is drying out, soft tissue, especially skin, is retracting,” Vreeman said. “The nails appear much more prominent as the skin dries out. The same is true, but less obvious, with hair. As the skin is shrinking back, the hair looks more prominent or sticks up a bit.”
Myth: Shaved hair grows back faster, coarser and darker.
Fact: A 1928 clinical trial compared hair growth in shaved patches to growth in non-shaved patches. The hair which replaced the shaved hair was no darker or thicker, and did not grow in faster. More recent studies have confirmed that one. Here’s the deal: When hair first comes in after being shaved, it grows with a blunt edge on top, Carroll and Vreeman explain. Over time, the blunt edge gets worn so it may seem thicker than it actually is. Hair that’s just emerging can be darker too, because it hasn’t been bleached by the sun.
Myth: Reading in dim light ruins your eyesight.
Fact: The researchers found no evidence that reading in dim light causes permanent eye damage. It can cause eye strain and temporarily decreased acuity, which subsides after rest.
Myth: Eating turkey makes you drowsy.
Fact: Even Carroll and Vreeman believed this one until they researched it. The thing is, a chemical in turkey called tryptophan is known to cause drowsiness. But turkey doesn’t contain any more of it than does chicken or beef. This myth is fueled by the fact that turkey is often eaten with a colossal holiday meal, often accompanied by alcohol — both things that will make you sleepy.
Myth: Mobile phones are dangerous in hospitals.
Fact: There are no known cases of death related to this one. Cases of less-serious interference with hospital devices seem to be largely anecdotal, the researchers found. In one real study, mobile phones were found to interfere with 4 percent of devices, but only when the phone was within 3 feet of the device. A more recent study, this year, found no interference in 300 tests in 75 treatment rooms. To the contrary, when doctors use mobile phones, the improved communication means they make fewer mistakes.
“Whenever we talk about this work, doctors at first express disbelief that these things are not true,” said Vreeman said. “But after we carefully lay out medical evidence, they are very willing to accept that these beliefs are actually false.”
