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9 Medical Myths Sat May 26, 2012 9:43 am
tobey_parker
1: Chocolate and Fried Foods Give You Acne
Some speculate that this myth dates back to the baby-boom generation, who had worse acne than their parents and also more access to chocolate and fried foods. Wherever this idea came from, it's wrong. Pimples form when oil glands under the skin produce too much of a waxy oil called sebum, which the body uses to keep skin lubricated. But when excess sebum and dead skin cells block pores, that area of the skin gets irritated, swollen, and turns red -- the telltale signs of a pimple. It is unknown why sebaceous glands produce excess sebum, but hormones are the prime suspects, which explains why teenagers are affected more than others. Stress and heredity may also be factors, but chocolate bars and onion rings are off the hook.
2: Coffee Will Sober You Up
If you've had too much to drink, no amount of coffee, soda, water or anything else is going to sober you up. The only thing that will do the trick is time. The liver can metabolize only about one standard drink (12 ounces of beer, 6 ounces of wine, or 1.5 ounces of hard liquor) per hour, so if you're drinking more than that every 60 minutes, you'll have alcohol in your system for some time. The idea of coffee's sobering effect may have started because caffeine acts as a stimulant, counteracting the sedative effect of alcohol to a small degree. However, it has no effect on the amount of alcohol in the blood. So if you've been drinking, spend your money on a cab rather than a cappuccino.
3: Cold Weather Can Give You a Cold
"Put your jacket on or you'll catch a cold!" How times have you heard that? You may not want to tell her this, but dear old Mom was wrong. Viruses (more than 200 different kinds) cause colds, not cold weather. In order for you to catch a cold, the virus must travel from a sick person's body to yours. This usually happens via airborne droplets you inhale when an infected person coughs or sneezes. You can also get a cold virus by shaking hands with an infected person or by using something where the virus has found a temporary home, such as a phone or door handle. Colds are more prevalent during the colder months because people tend to spend more time inside, making it much easier for viruses to jump from person to person.
4: Cracking Your Knuckles Causes Arthritis
The knuckles are the joints between the fingers and hand, and these joints contain a lubricant called synovial fluid. When you crack your knuckles, you are pulling apart two bones at the joint, which means the synovial fluid has to fill more space. This decreases the pressure of the fluid, and dissolved gases that are present, such as nitrogen, float out of the area in tiny bubbles. The bursting of these bubbles is the familiar sound we hear when someone "cracks" his or her knuckles. This bubble-bursting is not the same as arthritis, which is when the body's immune system attacks joints. However, constant knuckle-cracking can injure joints and weaken fingers.
5: Too Much Sugar Makes Kids Hyperactive
Many parents limit sugary foods, thinking they cause hyperactivity. It's right to restrict these treats, but the reasoning is wrong. These high-calorie foods offer little nutrition and can lead to obesity and other problems, but no scientific evidence says sugar causes hyperactivity. Sugar can provide a short-term energy boost, but that isn't the same as hyperactivity. The children at a birthday party acting like little tornadoes probably has more to do with the excitement of being around other kids, rather than the cake. And that unruly child in the grocery store throwing a fit with a sucker in his mouth and candy clutched in each fist? His parents probably haven't set appropriate behavior limits, and they most likely give him what he wants -- which is more candy.
6: Don't Swallow Gum -- It Takes Seven Years to Digest
Some misconceptions are hard to swallow, but people have been chewing on this one for years. This myth has probably been around since chewing gum became popular in the late 19th century and most likely originated thanks to a single word: indigestible. Gum is comprised of flavor, sweeteners, softeners and gum base. The body is able to break down the first three ingredients, but gum base is indigestible. That simply means your body can't dissolve it and extract nutrients. In the end, gum base works its way through your digestive system much like fiber -- in two or three days it goes out in basically the same shape it went in.
7: Feed a Cold and Starve a Fever
This bit of folk wisdom has been bouncing around for centuries. This advice may have evolved from the idea that illnesses could be classified as either low temperature (those that give chills, such as a cold) or high temperature (those with fever). With chills, it sounds reasonable to feed a person's internal fireplace with food. The logic follows that when an illness raises the body's temperature, cutting back on the "fuel" should help. However, scientific evidence doesn't endorse this advice -- many illnesses must simply run their course.
Nevertheless, if you're stuck in bed with a cold and a loved one brings over your favorite healthful foods, it's still OK to chow down. Alternatively, you may lose your appetite while fighting a fever-based sickness. When you're sick, it's okay to miss a meal or two as long as you are keeping up with fluid intake.
8: Wait 30 Minutes After Eating Before Swimming
For a kid, nothing ruins the fun of a carefree summer day like a worried parent banning swimming right after the big cookout, fearing that the child will get cramps and drown. There is a slight chance of minor abdominal cramping, but for the vast majority of people, this isn't dangerous. The body does divert blood flow from the muscles to the gastrointestinal system to spur digestion, but not in amounts that diminish muscle function. Listen to your body and swim when you're comfortable -- just like you probably don't run a marathon right after Thanksgiving dinner, you don't want to start swimming laps right after a seven-course picnic. It's perfectly safe, though, to eat a light meal and then get wet. After all, athletes commonly eat right before competing.
9: You Can Get the Flu from a Flu Shot
Vaccinations are misunderstood because they're created from the offending viruses themselves. But when you get a flu shot, you're not being injected with a whole virus -- you're receiving an inactivated, or dead, virus. That means the part of the virus that can infect you and make you sick is turned off, but the part of the virus that stimulates your body to create antibodies is still on. The body's antibodies will kill the flu virus should you come into contact with it later. Even pregnant women are advised to get flu vaccinations, so you know they're safe. The only people who should avoid them are those who have severe allergies to eggs, because eggs are used to create the vaccines. No vaccine is 100-percent effective, so there is still a chance you can get the flu after receiving the shot, but that doesn't mean the vaccination gave it to you.
Some speculate that this myth dates back to the baby-boom generation, who had worse acne than their parents and also more access to chocolate and fried foods. Wherever this idea came from, it's wrong. Pimples form when oil glands under the skin produce too much of a waxy oil called sebum, which the body uses to keep skin lubricated. But when excess sebum and dead skin cells block pores, that area of the skin gets irritated, swollen, and turns red -- the telltale signs of a pimple. It is unknown why sebaceous glands produce excess sebum, but hormones are the prime suspects, which explains why teenagers are affected more than others. Stress and heredity may also be factors, but chocolate bars and onion rings are off the hook.
2: Coffee Will Sober You Up
If you've had too much to drink, no amount of coffee, soda, water or anything else is going to sober you up. The only thing that will do the trick is time. The liver can metabolize only about one standard drink (12 ounces of beer, 6 ounces of wine, or 1.5 ounces of hard liquor) per hour, so if you're drinking more than that every 60 minutes, you'll have alcohol in your system for some time. The idea of coffee's sobering effect may have started because caffeine acts as a stimulant, counteracting the sedative effect of alcohol to a small degree. However, it has no effect on the amount of alcohol in the blood. So if you've been drinking, spend your money on a cab rather than a cappuccino.
3: Cold Weather Can Give You a Cold
"Put your jacket on or you'll catch a cold!" How times have you heard that? You may not want to tell her this, but dear old Mom was wrong. Viruses (more than 200 different kinds) cause colds, not cold weather. In order for you to catch a cold, the virus must travel from a sick person's body to yours. This usually happens via airborne droplets you inhale when an infected person coughs or sneezes. You can also get a cold virus by shaking hands with an infected person or by using something where the virus has found a temporary home, such as a phone or door handle. Colds are more prevalent during the colder months because people tend to spend more time inside, making it much easier for viruses to jump from person to person.
4: Cracking Your Knuckles Causes Arthritis
The knuckles are the joints between the fingers and hand, and these joints contain a lubricant called synovial fluid. When you crack your knuckles, you are pulling apart two bones at the joint, which means the synovial fluid has to fill more space. This decreases the pressure of the fluid, and dissolved gases that are present, such as nitrogen, float out of the area in tiny bubbles. The bursting of these bubbles is the familiar sound we hear when someone "cracks" his or her knuckles. This bubble-bursting is not the same as arthritis, which is when the body's immune system attacks joints. However, constant knuckle-cracking can injure joints and weaken fingers.
5: Too Much Sugar Makes Kids Hyperactive
Many parents limit sugary foods, thinking they cause hyperactivity. It's right to restrict these treats, but the reasoning is wrong. These high-calorie foods offer little nutrition and can lead to obesity and other problems, but no scientific evidence says sugar causes hyperactivity. Sugar can provide a short-term energy boost, but that isn't the same as hyperactivity. The children at a birthday party acting like little tornadoes probably has more to do with the excitement of being around other kids, rather than the cake. And that unruly child in the grocery store throwing a fit with a sucker in his mouth and candy clutched in each fist? His parents probably haven't set appropriate behavior limits, and they most likely give him what he wants -- which is more candy.
6: Don't Swallow Gum -- It Takes Seven Years to Digest
Some misconceptions are hard to swallow, but people have been chewing on this one for years. This myth has probably been around since chewing gum became popular in the late 19th century and most likely originated thanks to a single word: indigestible. Gum is comprised of flavor, sweeteners, softeners and gum base. The body is able to break down the first three ingredients, but gum base is indigestible. That simply means your body can't dissolve it and extract nutrients. In the end, gum base works its way through your digestive system much like fiber -- in two or three days it goes out in basically the same shape it went in.
7: Feed a Cold and Starve a Fever
This bit of folk wisdom has been bouncing around for centuries. This advice may have evolved from the idea that illnesses could be classified as either low temperature (those that give chills, such as a cold) or high temperature (those with fever). With chills, it sounds reasonable to feed a person's internal fireplace with food. The logic follows that when an illness raises the body's temperature, cutting back on the "fuel" should help. However, scientific evidence doesn't endorse this advice -- many illnesses must simply run their course.
Nevertheless, if you're stuck in bed with a cold and a loved one brings over your favorite healthful foods, it's still OK to chow down. Alternatively, you may lose your appetite while fighting a fever-based sickness. When you're sick, it's okay to miss a meal or two as long as you are keeping up with fluid intake.
8: Wait 30 Minutes After Eating Before Swimming
For a kid, nothing ruins the fun of a carefree summer day like a worried parent banning swimming right after the big cookout, fearing that the child will get cramps and drown. There is a slight chance of minor abdominal cramping, but for the vast majority of people, this isn't dangerous. The body does divert blood flow from the muscles to the gastrointestinal system to spur digestion, but not in amounts that diminish muscle function. Listen to your body and swim when you're comfortable -- just like you probably don't run a marathon right after Thanksgiving dinner, you don't want to start swimming laps right after a seven-course picnic. It's perfectly safe, though, to eat a light meal and then get wet. After all, athletes commonly eat right before competing.
9: You Can Get the Flu from a Flu Shot
Vaccinations are misunderstood because they're created from the offending viruses themselves. But when you get a flu shot, you're not being injected with a whole virus -- you're receiving an inactivated, or dead, virus. That means the part of the virus that can infect you and make you sick is turned off, but the part of the virus that stimulates your body to create antibodies is still on. The body's antibodies will kill the flu virus should you come into contact with it later. Even pregnant women are advised to get flu vaccinations, so you know they're safe. The only people who should avoid them are those who have severe allergies to eggs, because eggs are used to create the vaccines. No vaccine is 100-percent effective, so there is still a chance you can get the flu after receiving the shot, but that doesn't mean the vaccination gave it to you.
