Mental Floss

THE BODY

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12 Intriguing Facts About the Intestines

We only think about our intestines when we have intestinal pain, or when something else goes wrong. But scientists are finding intriguing links between your gut, brain, and other systems.

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11 Facts About the Kidneys

Your kidneys filter almost 50 gallons of blood a day to keep your whole body healthy. Read on for more facts about this crucial organ—including what causes kidney stones.

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11 Squeaky-Clean Facts About Spit

Saliva is more important than you think: You need spit to taste, chew, swallow, and digest everything you eat. Your spit even fights tooth decay and cavities.

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12 Facts About the Sense of Taste

It goes way beyond your taste buds.

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12 Facts About the Pancreas

Without this important gland, you'd be diabetic.

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14 Facts About Feet

Those 52 foot bones do a lot of heavy lifting.

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11 Insightful Facts About Eyes

See how many you know.

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11 Facts About Eczema

Scratching makes it worse.

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13 Facts About Ovaries

They're tiny but mighty.

Colorized scanning electron micrograph of E. coli, a common gut bacteria

10 Smart Facts About Your Gut

Your gut has millions of neurons. And that's just one of its intelligent features.

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What Causes Hiccups?

The answer depends on whom you ask.

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12 Facts About Belly Buttons

The ins and outs.

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The Surgeon Who Removed His Own Appendix

They call it the "practice" of medicine for a reason.

Chloe Effron

Why Is Pee Yellow?

It is possible for urine to be different colors. But yellow pee is a sign that your body is healthy.

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12 Facts About Kidney Stones

They’re more common than ever.

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Here’s What Happens to Your Body During Anaphylaxis

This is the science of it, step by step.

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12 Facts About the Gallbladder

It's that little organ you may have forgotten about.

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6 Signs You're Getting Hangry

Check yourself before you wreck yourself.

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11 Facts About Fingernails

They're more than just a place to dab polish.

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Thousands of Swedes Are Replacing Their ID Cards with Microchip Implants

Wasn't this an episode of 'Black Mirror'?

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Two Human Toes Were Stolen From an Anatomy Exhibit

The digits are valued at about $3800.

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11 Facts About the Appendix

It has a function after all.

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What's Really Happening When We See 'Stars' After Rubbing Our Eyes?

Don't worry—it's perfectly normal.

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Why Your Knuckles Make That Satisfying Cracking Sound, According to Science

One of life's most pressing questions, explained.