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We share 90% of our DNA with cats - We are genetically closer to cats than we are to dogs.

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Bagel-related injuries - In 2008 almost 2,000 people in the US went to the hospital with bagel-related injuries.

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Cholesterol and violence - A study shows that there is a link between individuals with low cholesterol levels and violent crime.

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Women have "younger" brains - A study found that women's metabolic brain age is about four years younger than men's.

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Heart and music - Music tempo and volume has a direct impact on heart rate. This means that fast music played at high volume will increase your heartbeat, and the opposite is also true.

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Sense of smell - You lose your sense of smell when you're asleep.

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Microorganisms - We have trillions of microorganisms in our bodies, but a study found that more than 99% are unknown to science.

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Poop transplant - Fecal transplantation, also known as bacteriotherapy, is when healthy fecal bacteria is transplanted to a person requiring treatment. It can be done through a colonoscopy or through pills.

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We breath out excess weight - When we lose weight, fat cells turn into carbon dioxide and are then expelled through our lungs.

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A fetus will cure mom's heart - If a pregnant woman has damaged heart tissue, the fetus will donate stem cells to heal it.

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Cornea -

The cornea has no blood vessels, so it needs to get oxygen directly from air.

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Contralateral lung transplantation - When a lung transplant is required but the organ available is from the opposite side, surgeons flip it and attach it (i.e. left lung on the right side).

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Male soldiers with breasts - Germany's Wachbataillon military guards are growing breast tissue on the left side of their chests. Doctors say this is because of the drill they do, where they hit that area repeatedly with their rifles.

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Gas - If you don't fart, some gas may re-enter your blood stream and it will be released through your breath.

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Redheads - Redheads experience pain differently from other people. They actually need around 20% more anesthesia to feel no pain.

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Gut feeling -

Your brain and your gut are actually connected. It's called the gut-brain axis.

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Gamers make good surgeons - A study shows that surgeons who played video games regularly had better laparoscopic surgical skills.

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Fingernail and toenail regrow rate - If you lose a fingernail, it will take six months to regrow, but in the case of a toenail, it can take up to a year and a half!

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Sweaty feet -

A pair of feet has approximately 250,000 sweat glands. This is where most of your sweat glands are located.

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Retained surgical items - In the US alone, every year about 2000–4000 objects are left inside patients' bodies after surgeries.

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Extra bones - Adults have 206 bones. But we are actually born with 300 bones! Most of these are in fact cartilage that will then fuse and turn into bones.

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Tongue is the new fingerprint - Everyone has unique fingerprints, but the tongue also has a unique print.

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Alcohol prescribed by doctors - Alcohol is sometimes prescribed to alcoholics before surgical procedures to avoid withdrawal symptoms.

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Three kidneys -

When performing kidney transplants, many times the diseased organ is not removed. Instead, a third kidney is added.

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My baby's poop is better than yours - Mothers prefer the smell of their own babies' poop, and don't find the smell as bad as other children's feces.

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Your liver has a superpower - Livers have the ability to regenerate. This mean they will regrow if parts are removed.

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Oops, that's the wrong leg! - Wrong-site surgery in orthopedics is more common than you might think.

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Medical malpractice -

According to a 2017 report, 55% of physicians in the US have been sued for malpractice.

See also: What are the worst pains that humans can suffer?

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