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Myth: Drinking a lot of hot, black coffee will help you sober up after drinking a lot of alcohol.
This question has been discussed by everyone from college students to respected scientists, probably for generations. Like many medical myths there is some “truth” to this notion. However, Dr. Martin Carey of UAMS' Department of Emergency Medicine says it's important to know that coffee cannot reverse the effects of alcohol. “It cannot ‘sober you up.’ It does not get rid of alcohol from the system,” stresses Dr. Carey. “If you have an alcohol level above the legal limit, you can drink all the coffee you want and the alcohol level will not magically fall faster than it would have if you had not drunk the coffee. That said, there must have been some effect produced by the coffee that has led people to believe that there is an effect. This has been extensively studied, and it appears that the effect is due to a partial reversal of the sedating effect of the alcohol. Persons who were below the legal limit for driving were tested, with and without coffee. They appeared to perform better on tests of concentration after the coffee than before."
Myth: Drinking eight glasses of water a day is good for your overall health and will prevent kidney stones.
Reality: Everyone has heard that we should drink eight glasses of water a day but there's no way to determine where this belief originated nor has there ever been a scientific study to support it, explains Dr. Alex Finkbeiner, chairman of the UAMS Department of Urology. "Interestingly, one of my colleagues also questioned whether such a statement was true and, after conducting a research study, concluded there is no basis for such a statement. I advise patients to simply let their thirst guide their fluid intake unless there is a specific medical reason to do differently." Fluid intake is, however, a key to reducing kidney stone formation. "Urine is water with salts dissolved in it. Stones form when the salts come out of solution and coalesce together, just like the crust you see at the bottom of a tea kettle after boiling tap water," says Dr. Finkbeiner. "Physical chemistry teaches us that salts stay in solution more readily if they are suspended in a greater volume of water. Stones generally form when you are relatively dehydrated and your urine becomes concentrated." So, how much water should you drink to reduce kidney stones? "It depends on your environment and activity. A simple rule is drink enough to keep your urine looking like water. Avoid letting your urine turn dark yellow or golden brown, that means it's too concentrated."
Myth: A woman who has never given birth is more likely to develop ovarian or uterine cancer than a woman who has had a child.
Reality: In ovarian cancer, the likelihood of developing the disease is reduced with each pregnancy, says Dr. Alexander Burnett, chief of UAMS' Division of Gynecologic Oncology. "Also, if a woman takes birth control pills for at least five years during her reproductive life, she will have a reduced chance of developing ovarian cancer. It appears that women who have continuous ovarian cycles with monthly ovulation are at increased risk for ovarian cancer. These conditions – pregnancy and oral contraceptive pills – provide a break from the continuous cycles and are theorized to reduce cancer by some related, as yet defined, mechanism." As for uterine cancer, the main risk factor is prolonged exposure to estrogen. "This can be due to excess body fat, taking estrogen medications without progesterone, or situations where the uterus is continuously exposed to the woman’s own estrogens," says Dr. Burnett. "Statistically, women who have children are at lower risk than women who have never given birth. It is theorized that pregnancy provides a period of endometrial 'rest.'"
Myth: Feeding a child a lot of candy or food with a lot of sugar in it will make them hyperactive.
Reality: No evidence exists that feeding children a high-sugar diet will induce hyperactivity, despite the common belief that it does, according to Dr. Bryan Burke, an associate professor of General Pediatrics and Neonatology at UAMS. "By the same token I kind of like this old wive's tale, despite it being wrong, because a high-sugar diet has its own problems even if you discount hyperactivity. Our children are living in an age conducive to obesity - how could one ever argue against decreasing an excessive amount of dietary sugar?" Dr. Burke warns parents not to worry just about their children's sugar intake. "An excessive amount of fat can just as easily make one overweight. Moderation in all things is the best advice."
Myth: Some people can be carriers of diseases without ever appearing sick.
Reality: Infections are transmitted by different types of "germs,, including bacteria and viruses. Some germs can cause asymptomatic infection, which means that the person can have the "germ" in their body, but they don't have any symptoms of the disease or they have very mild symptoms and don't really feel sick, says Dr. Anupama Menon of UAMS' Division of Infectious Diseases. "And if the particular 'germ' can be transmitted by coughing or sneezing, for example, then the person may transmit the infection to someone else without knowing it and without having any symptoms themselves," says Dr. Menon. Other types of infections make everyone who gets exposed become symptomatic, in other words. to feel sick. Some of these can also be transmitted from person to person. As for viruses that cause colds, people can, in fact, transmit these viruses with mild or minimal symptoms themselves. In this case, they're considered asymptomatic carriers. They usually don't have the virus in their system for a prolonged period of time, though.
Myth: Your heart stops for an instant whenever you sneeze.
Reality: When a person sneezes, they increase their intrathoracic pressure and can decrease venous blood flow back to the heart, according to Dr. Chris Danner of UAMS’ Department of Otolaryngology/Head and Neck Surgery. "The heart may compensate for this by a slight change in its beating rate, but the heart and its electrical activity should not stop during a sneeze," says Dr. Danner.
Myth: Taking vitamin C will help you avoid getting a cold.
Reality: Vitamin C, also known as ascorbic acid, is good for preventing scurvy, which British sailors discovered in the mid-1700s. However, it won’t prevent colds or relieve any of the symptoms associated with them, says Dr. Charles Born of the UAMS College of Pharmacy. Many people are convinced that taking large quantities of vitamin C will keep them from getting sick, according to Born. To test this theory, several large-scale, controlled studies involving children and adults have been conducted. To date, no conclusive data has shown that large doses of vitamin C prevent colds. The vitamin may reduce the severity or duration of symptoms, but there is no clear evidence. “Taking vitamin C over long periods of time in large amounts may actually be harmful,” Dr. Born says. “Too much vitamin C can cause severe diarrhea, a particular danger for elderly people and small children."
Myth: Blowing smoke into a child's ear to cure an infection is dangerous because it can lead to hearing loss.
Reality: The normal course of a middle ear infection is for puss or infection to build up behind the ear, says Dr. Danner. “This pressure causes severe discomfort. The ear drum will then rupture relieving the pressure and pain. The ear drum will then heal. The majority of ear infections will resolve in this manner. Antibiotics only minimally decrease the healing time.” Blowing smoke in the ear will do nothing to speed the resolution of the infection and will cause no harm to the ear, Dr. Danner explains. “It will not make the ear better or worse,” Dr. Danner says. “The only thing blowing smoke into the ear will do is increase the physical and emotional bonds between the parent and the sick child and increase the risk of the parent acquiring lung disease.”
Myth: Wearing a copper bracelet can cure arthritis.
Reality: Arthritis is a condition that results in deterioration and loss of the joint surface cartilage, basically the repair process fails to keep up with the breakdown. Copper bracelets have long been sold as a cure for arthritis, vendors propose that the metal is absorbed through the skin and helps cartilage regeneration. But there are certain facts you should know before you rush out and buy that bracelet, says Dr. Randy Bindra, director of the Center for Hand and Upper Extremity Surgery at UAMS. “Copper is a component of some of the normal cellular enzymes and we require very small amounts of copper in our daily diet,” says Dr. Bindra. Mineral-rich foods include vegetables (potatoes), legumes (beans and peas), nuts (peanuts and pecans), grains (wheat and rye) and fruits (peach and raisin). “Copper deficiency is extremely rare and most regular diets provide enough copper to meet the daily requirements. Supplementation is only needed in patients with other serious medical conditions that affect their gastrointestinal tract and impair their ability to absorb nutrients.” While it’s never been proven that copper can copper be absorbed through the skin by wearing a bracelet, research has shown that excessive copper can result in poisoning, causing vomiting and, in severe cases, liver damage. “This can be seen after ingesting foods boiled in copper vessels or from contamination of water from corroding copper pipes. In reality no modality of treatment has been shown to cure or reverse the changes of arthritis,” says Dr. Bindra.
Myth: Spinach is a great source of iron.
Reality: Despite what Popeye led a lot of young people to believe, spinach is not particularly rich in iron. In reality, it has about the same iron content as any other green vegetable, according to Dr. Philip Kern of UAMS’ Division of Endocrinology. “Spinach also contains oxalic acid, which prevents more than 90 percent of the iron from being absorbed by the body,” says Dr. Kern. However, spinach is rich source of vitamin A, vitamin E and several vital antioxidants, with more than a half-day’s supply of beta carotene found in just a half cup of the vegetable, adds Dr. Kern. (The idea that spinach contained exceptional levels of iron originated in 1870 with Dr. E. von Wolf whose figures remained unchallenged until 1937, when it was discovered that the content was 1/10th the claim. The oversight resulted from a misplaced decimal point.)
Myth: Feed a cold and starve a fever.
Reality: A common cold is an illness caused by a virus infection located in the nose. The symptoms of a common cold include sneezing, runny nose, nasal congestion, a sore or scratchy throat, coughing, hoarseness, often accompanied by headache, feverishness, chilliness and a general sense of not feeling well. Not only is it a bad idea to starve a fever, it will hinder your ability to recover from the cold, according to Dr. Kern. “Drinking plenty of fluids is important since fever promotes fluid loss from the body and dehydration can result,” Dr. Kern says. While drinking or eating hot or cold foods affects the temperature of the mouth, it will have no effect on a person’s overall body temperature. Dr. Kern adds that another popular belief, that chicken soup is good for a cold, is actually true to a certain extent, as drinking warm liquids such as soup helps open up the nasal passages. This allows the patients to breathe easier and get the rest needed to fully recuperate.
Myth: You can get the flu by getting a flu shot.
Reality: The best way to avoid getting the flu is to get the influenza vaccine, available by shot or by nasal spray, each fall before the flu season starts. “The vaccines work by exposing your immune system to the flu virus. Your body will build up antibodies to the virus to protect you from getting the flu. The flu shot contains dead viruses while the nasal-spray vaccine contains live but weakened viruses,” says Dr. Charles Smith, medical director for UAMS Medical Center. In other words, says Dr. Smith, you cannot get the flu from a flu shot or the nasal-spray vaccine. Some people who get the vaccine will still get the flu, but they will usually get a milder case than people who aren't vaccinated, adds Dr. Smith. The vaccine is especially recommended for people who are more likely to get really sick from flu-related complications.
Myth: You can catch poison ivy if you come into contact with someone who has been exposed to it.
Reality: This is partly true, partly myth. The poison ivy rash itself is not contagious, according to Jerri Hoskyn, M.D., an assistant professor of dermatology at UAMS. Neither will fluid from the blisters of a poison ivy rash spread poison ivy. “The poison ivy rash is caused by contact with urushiol, the oil from the leaves of the poison ivy plant. Only urushiol can cause the rash. By the time the rash has appeared, the urushiol is usually no longer present on the skin, which is why the rash is not contagious. However, poison ivy can be transmitted when urushiol on one person’s skin or clothing, an animal’s fur, or even on an inanimate object rubs off onto another person’s skin, causing them to develop the poison ivy rash.”
Myth: Cold, wet weather causes colds and flu.
Reality: Colds are really upper respiratory infections and can result from more than 200 different viruses. These include the rhinoviruses, the group most often associated with the common cold, which primarily affects the nose and throat. According to Robert Bradsher, M.D., director of UAMS’ division of infectious diseases, cold weather usually makes people stay indoors, which might increase the person-to-person transmission of respiratory viruses. “These viruses, including influenza, are very infectious and are transmitted from one person to the next by touching something that has had the respiratory virus on it and then touching your eye or nose or mouth. Some believe that the lower humidity during the winter allows these viruses to persist longer in the environment. Washing your hands or using an alcohol-based hand washing solution is a good way to avoid getting a cold.”
Myth: Putting butter on a burn will ease the pain.
Reality: Hoskyn says that immediately after receiving a burn, it is important to cool the skin in order to stop the burning process. Putting butter or other greasy ointments on a burn may actually make things worse, since the grease will slow the release of heat from the skin, allowing damage to the skin from the burn to continue. The best way to cool the skin after a burn is with cool water, not ice or ice water. An antibiotic ointment and a bandage will aid the healing process. According to Hoskyn, leave the butter for your toast.
Myth: Reading in dim light ruins your eyesight.
Reality: As a rule, you cannot damage your eyes by using them, according to Nicola Kim, M.D., an assistant professor of ophthalmology at UAMS’ Jones Eye Institute. “There are a few specific exceptions, like looking directly into sunlight and laser light, but other than this, reading in dim or bright light will not change the health or function of your eyes. It may feel more difficult to focus if the lighting is suboptimal, but this has no permanent effect on the structure of your eyes. In addition, any challenging visual activity will generally decrease a person’s blink rate and lead to discomfort from drying. This is obviously temporary and easily treated with lubricating eyedrops. Likewise, sitting too close or too far from the TV will also have no permanent effect on your vision.”
Myth: Hair and fingernails continue to grow after death.
Reality: Hair and fingernails may appear longer after death, not because they have grown, but because the skin around them has retracted, according to Hoskyn. After death, dehydration causes the skin and other soft tissues shrink, while the hair and nails remain the same length, thus creating the optical illusion of growth.
Myth: If you eat too many carrots, your skin will turn orange.
Reality: Eating too many carrots, or other foods high in beta-carotene, can cause a condition called carotenemia, explains Hoskyn. “High levels of beta-carotene can cause a yellowish discoloration of the skin, most noticeable on the palms and soles. Unlike jaundice, though, carotenemia does not cause yellowing of the whites of the eyes. Carotenemia is usually seen in young children, is not toxic and generally does not cause other health problems. The treatment is a low-carotene diet, but it may take several months for the skin to return to its normal color. But don’t substitute tomatoes for your carrots! Too many tomatoes can cause a yellow-orange discoloration of the skin called lycopenemia, due to the accumulation of lycopene in the tissues. The treatment for lycopenemia is also dietary modification.”
Myth: Cracking your knuckles causes arthritis.
Reality: There's no evidence that knuckle cracking causes arthritis but it may cause temporary soreness of the joint. Knuckles are the joints that connect your fingers to your hand. These joints are surrounded and lubricated by synovial fluid, a thick, clear liquid. When you crack your knuckles, you're causing the bones of the joint to pull apart. This causes a gas bubble to form in the joint. The cracking or popping sound you hear is the breaking of the adhesive seal in the joint. It may take awhile for the joint to reseal before you can crack your knuckles again. The repetitive motion of cracking wears down the joints and their protective cushioning, so the habit could worsen osteoarthritis, but plays no role in rheumatoid arthritis, which is caused when a person's own immune system attacks the joints.
Myth: Eating chocolate causes acne.
Reality: Although “acne diets” prohibiting chocolate and other goodies were popular years ago, the good news for acne patients is that dermatologists these days no longer recommend acne diets, reports Hoskyn “Currently, there is no good evidence to link chocolate or other specific foods to acne. Acne treatments today focus on keeping the pores open and controlling oil production and bacteria in the skin.”
Myth: If a woman carries her baby high in the uterus and her stomach has a round appearance, she is expecting a girl. Likewise, a boy is carried low and relatively more sideways.
Reality: The gender is determined at time of conception, explains Helen Kay, M.D., chairman of the department of obstetrics and gynecology. “Boy babies tend to be bigger but that shouldn’t affect the way they lay within the uterus. This is more dependent on the mother’s uterus rather than the gender of the baby.”
Myth: You can catch a venereal disease by using a public restroom.
Reality: Venereal diseases, or more recently called sexually transmitted diseases, are transmitted by direct contact with the bacteria or virus that is the specific cause of specific diseases, according to Bradsher. “We tend to say in medicine, ‘never say never,’ when asked about the possibility of something, but in order to ‘catch VD from a toilet seat,’ you would have to have direct contact at the site on the skin with the microbial pathogen. This would very rarely, if ever, occur.”
Myth: Shaving hair causes it to grow back faster, darker and coarser.
Reality: Shaving does not cause hair to grow back faster, darker or coarser. “Shaving is just a method of cutting the hair at the skin surface and has no effect on the part of the hair shaft below the skin surface, which is where growth and pigmentation occur,” says Hoskyn. “Although the hair may seem to grow faster after shaving, this is just an illusion: a small amount of growth on a clean-shaven face is much more noticeable than a small amount of growth on a bearded face. Likewise, the blunt, stubbly ends of new growth can give the illusion of darker, coarser hair.”
Myth: It's OK to smoke prior to having surgery, as long as you don't have more than one cigarette.
Reality: Research has shown that there is no safe minimum amount of smoking prior to surgery, says Dr. Julio Hochberg of UAMS' Division of Plastic and Reconstructive Surgery. "Patients that smoke have 10 times more surgical complications than a non-smoker," says Hochberg. "Smokers that smoke between three to nine cigarettes a day have the same risk as those who who reported smoking more than 30 cigarettes a day. Only one cigarette remains in the system for 14 days. If you smoke one pack a day, you have at any given time 14 packs of cigarettes in your system. And if it contains menthol, the cigarette will remain for 20 days."
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