Elliott: Hi, I'm Elliott, this is mental_floss on YouTube, and today, I'm going to talk about some misconceptions about allergies. 

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Misconception #1: Blood tests are the best way to determine food allergies.  Actually, 50-60% of blood tests will give a false positive result when it comes to food allergies.  The best way to find out if someone is allergic to food is to do a test called an oral food challenge, which I know sounds like a challenge some YouTuber made up, but I promise it's real.  In an OFC, an allergist feeds their patient small doses of whichever food is thought to be an allergen.  After observation, the dose is increased.  This gets repeated.   Of course, if a reaction shows, the patient gets treated, and if there's no reaction, then there's no allergy, congratulations!

Misconception #2: Food allergies are uncommon.  According to the Food Allergy Research and Education Organization, 15 million people in the United States suffer from a food allergy.  Even more surprising is that 1 in 13 kids has one.  In case you're starting wonder if you may be one of those people, I'll let you know what you should look for.  90% of food allergies are one of these eight foods: milk, soy, eggs, wheat, peanuts, tree nuts, fish, and shellfish.

Misconception #3: Penicillin allergies are common.  You might think you're allergic to Penicillin just like 1 in 10 adults who claim to be, but don't be so sure.  In a study done at the Cleveland Clinic, 21 of 24 patients who said that they were allergic to Penicillin received negative results when they were given a skin test.  So almost 90% of them were wrong about their allergy.  This is probably because they had a reaction to the drug when they were younger, but allergies sometimes just go away, which brings me to...

Misconception #4: Allergies are for life.  Some people develop allergies as they get older, on the other hand, some people just outgrow allergies.  In fact, over a quarter of children in the US outgrow their food allergies.  It typically happens before they turn 10 years old, but it could happen at any time.

Misconception #5: People who are allergic to shellfish can't do CT scans.  Some people believe that their shellfish allergy means they shouldn't have a computerized tomography scan.  Before a CT scan, a patient must ingest or be given a dye or contrast, which contains iodine.  Shellfish also contain iodine, but studies show that people who are allergic to shellfish are actually intolerant of proteins in the animals rather than iodine, but some doctors still will avoid giving these patients a contrast with iodine in it.

Misconception #6: Babies shouldn't be given allergenic foods before they turn one.  The American Academy of Allergy, Asthma, and Immunology recommends exactly the opposite.  They claim that giving babies food like peanut butter, fish, and eggs when they're four to six months old might actually help prevent future food allergies, but this is a relatively new finding and it hasn't been thoroughly studied, so if you have a baby, you should probably just like, talk to your doctor, okay, and see what they say about this kind of stuff, they're usually really smart, they went to a lot of school.

Misconception #7: Allergic reactions come from allergens.  You can actually blame your immune system for those pesky hives.  Once your body inhales, eats, or comes into contact with an allergen, the immune system misidentifies it as this harmful substance.  Then, it makes antibodies which attack the allergen, so the allergen isn't attacking your body, it's actually the other way around.

Misconception #8: You know how you'll react to an allergen.  Allergies are unpredictable.  Someone who usually has a minor intolerance to an allergen still risks a more serious reaction, like anaphylaxis.

Misconception #9: Animal hair is an allergen.  If you're allergic to an animal, it's probably their dander, saliva, and/or urine, gross, that's giving you trouble.  Dander gets shed from the body, and it's made of skin cells, and it contains proteins that some immune systems don't like, but I should mention that animal hair can contain dander or other allergens including pollen and dust, so it's still worth vacuuming like, once every always.  Always vacuum.

Misconception #10: Mediation is the only way to treat allergies.  Some other treatment options include shots and sublingual immunotherapy, or if your allergies are seasonal or related to your home, you could try like a humidifier or maybe getting rid of your carpet or your dog.

Thanks for watching misconceptions on mental_floss on YouTube, which is made with the help of all of these nice people.  If you have a topic for an upcoming misconceptions episode that you would like to see, leave it in the comments, and I will see you next week.  Bye. 

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