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Most of us struggle to keep our weight down, but not Lizzie Velasquez. The 21-year-old woman from Austin, Texas actually has to eat every 15 minutes to say alive. Miss Velasquez has a rare condition which prevents her from gaining weight, even though she eats up to 60 small meals a day.
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Mr Perry, 59, can eat whatever he likes - including unlimited pies, burgers and desserts - and never get fat. He cannot put on weight because of a condition called lipodystrophy that makes his body rapidly burn fat.
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Dutchman Wim Hof, also known as the Iceman, is the man that swam under ice, and stood in bins filled with ice. He climbed the Mt. Blanc in shorts in the icy cold, harvested world records and always stands for new challenges. Scientists can't really explain it, but the 48-year-old Dutchman is able to withstand, and even thrive, in temperatures that could be fatal to the average person.
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Rhett Lamb is often cranky like any other 3-year-old toddler, but there’s one thing that makes him completely different: he has a rare medical condition in which he can’t sleep a wink. Rhett is awake nearly 24 hours a day, and his condition has baffled his parents and doctors for years. They took clock shifts watching his every sleep-deprived mood to determine what ailed the young boy.
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Teenager Ashleigh Morris can't go swimming, soak in a hot bath or enjoy a shower after a stressful day's work - she's allergic to water. Even sweating brings the 19-year-old out in a painful rash.
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That's the story of AJ, an extraordinary 40-year-old married woman who remembers everything. McGaugh and fellow UCI researchers Larry Cahill and Elizabeth Parker have been studying the extraordinary case of a person who has "nonstop, uncontrollable and automatic" memory of her personal history and countless public events. If you randomly pick a date from the past 25 years and ask her about it, she’ll usually provide elaborate, verifiable details about what happened to her that day and if there were any significant news events on topics that interested her. She usually also recalls what day of the week it was and what the weather was like.
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Meet Natalie Cooper, a 17-year-old teenager who has a mystery illness that makes her sick every time she eats anything. Well, almost anything. She can eat one thing that doesn’t make her sick: Tic tac mint!
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Chris Sands, 24, from Lincoln, hiccups as often as every two seconds - and sometimes even when he is asleep. He has tried a variety of cures, including hypnosis and yoga, but nothing has worked. Mr Sands thinks his problem stems from an acid reflux condition caused by a damaged valve in his stomach. "If the acid levels are severe enough they are going to do keyhole surgery and grab part of my stomach and wrap it around the valve to tighten it," he said.
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Kay Underwood, 20, has cataplexy, which means that almost any sort of strong emotion triggers a dramatic weakening of her muscles. Exhilaration, anger, fear, surprise, awe and even embarrassment can also cause sufferers to suddenly collapse on the spot. Kay, of Barrow-upon-Soar, Leicestershire (UK), who was diagnosed with the condition five years ago, once collapsed more than 40 times in a single day. She said: "People find it very odd when it happens, and it isn't always easy to cope with strangers' reactions. "
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For most people talking on a mobile phone, cooking dinner in the microwave or driving in a car is simply part of modern living in 21st century Britain. But completing any such tasks is impossible for Debbie Bird - because she is allergic to Cell Phones and Microwaves.
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UK's Sarah Carmen, 24, is a 200-a-day orgasm girl who gets good, good, GOOD vibrations from almost anything. She suffers from Permanent Sexual Arousal Syndrome (PSAS), which increases blood flow to the sex organs. "Sometimes I have so much sex to try to calm myself down I get bored of it. And men I sleep with don't seem to make as much effort because I climax so easily."