Some medical myths are accepted as fact by many of us, including doctors. Here are common misconceptions about our health and the truth behind them…
Myth: If your mucus is green, you have a sinus infection.
Reality: It is not worth checking your tissue after you blow your nose — the color of mucus has nothing to do with whether you have an infection or not.
Lots of doctors fall for this one. A survey published in The Lancet found that doctors are seven times more likely to prescribe an antibiotic to patients with colored nasal discharge than to those whose mucus is clear.
Nasal discharge may become thick and turn yellow or green in color as the common cold runs its course, but research has shown that mucus color does not determine the need for antibiotics. In a study published in International Journal of Pediatric Otorhinolaryngology, 142 children with green nasal discharge were given either an antibiotic alone… an antibiotic with a combination decongestant and antihistamine… or a placebo. After six days, there was no difference in cold symptoms or nasal discharge in any of the groups. The only difference was that more side effects were seen in those who took the antihistamine and decongestant. Other studies have shown that antibiotics do not shorten the duration of a cold or other illness in which green mucus is a symptom.
So how do you know if you have a sinus infection? A cold lasting more than seven to 10 days and sinus pressure or pain with a fever could indicate a bacterial infection for which an antibiotic may be needed.
Myth: If you touch someone with poison ivy, you’ll catch it.
Reality: The poison ivy rash is not contagious — even the oozing blisters are not contagious. You cannot spread the poison ivy rash from one part of your body to another by touching or scratching it.
However, the oil urushiol, from the poison ivy plant, can remain on your skin or clothes. If someone touches the oil, he/she can get the rash, too. Taking a shower and washing with soap effectively removes oil from the body. Wash all contaminated clothes (separately from other clothes) in the washing machine.
Myth: If you pull out a gray hair, two will grow back in its place.
Reality: Although gray hairs may seem to proliferate before your eyes, this is not the case. Each hair on your body grows out of its own follicle. Plucking one hair will not make two hairs grow back out of a single follicle. However, it takes a long time for a hair to grow back — a rate of one centimeter (about one-third of an inch) per month — so in the time it takes for that gray hair to grow back, other gray hairs may have grown in around it. This could give the appearance that you caused a whole patch of gray by pulling out just one gray hair.
Myth: A dog’s mouth is cleaner than a human’s.
Reality: This myth may have started after some old studies found that wounds caused by human bites were more likely to become infected than ones caused by dog bites. More recent research found that those numbers may have been skewed due to one type of bite. Bites sustained to the hand from punching a person in the mouth are more liable to get infected. This is most likely due to the depth of the wound that results from this action. Any other type of human bite is no more likely to become infected than a dog bite.
Myth: Poinsettias are poisonous plants.
Reality: This plant, commonly displayed in homes during the Christmas season, is not a health threat to people or pets. Researchers from the Pittsburgh Poison Center at University of Pittsburgh analyzed the outcomes of 22,793 cases of poinsettia exposures reported to the American Association of Poison Control Centers. The study, published in American Journal of Emergency Medicine, found no fatalities from eating or touching the plant. In fact, 96% of the patients (93.3% were children) did not require any medical care. The worst that is likely to happen if a child, pet or an adult were to eat a large amount of poinsettia leaves — which, of course, is not recommended — is that it could lead to nausea and vomiting.
Myth: You lose most of your body heat through your head.
Reality: Many moms have gotten their kids to wear hats by saying that most of their body heat would escape from their heads if they didn’t. While moms mean well, they are wrong. And they are not the only ones — the US Army has perpetuated this myth, too. The army’s survival manual recommends keeping the head covered in cold weather because “you can lose 40% to 45% of body heat from an unprotected head.”
This myth most likely stems from a 50-year-old military study in which participants were exposed to extremely cold temperatures while wearing arctic survival suits that came to their necks. When heat loss was measured, not surprisingly most heat escaped from the head, which was the only part of their bodies not covered. Experts say that if you performed the same study on people wearing only bathing suits, they would not have lost any more heat proportionally from their heads than from any other part of their bodies.
A recent study published in Journal of Applied Physiology examined the effects of heat loss when the body is submerged in cold water. When the study participants’ heads were submerged, as opposed to just their bodies up to the neck, they did not lose relatively more body heat.
So the head is not special when it comes to getting cold. Any body part that is exposed to cold weather will cause a drop in body temperature.
Myth: You can get a hernia from lifting something heavy.
Reality: Lifting does not cause a hernia. A hernia is an opening or a weakness in the muscle wall of the belly or groin. It usually is a defect that did not close up during development or a type of weakness that runs in your family.
However, lifting can make the hernia more obvious to you. When you lift something heavy, it increases the pressure in your belly. If you already have a hernia, this type of increase in pressure can cause a little sac of your intestines to bulge out through the hole, becoming more prominent. But even if you never lifted anything or never engaged in any form of exertion, that defect or opening in your muscle wall still would be there — you still would have a hernia.
Also, in a study of 133 patients with hernias, 89% reported a gradual onset of symptoms for their hernias. Of the 11% of the people in the study who thought that their hernias were tied to exertion, the medical examiners could find no evidence to support this thinking.
