Goosebumps are a vestigial reflex from when human ancestors had more body hair to keep them warm.

Red blood cells complete a full circuit of the body in about 20 seconds.

Fact #3272 · Human Body

The human brain can process images in as little as 13 milliseconds.

Fact #2485 · Human Body

Your bones constantly rebuild themselves.

Fact #2472 · Human Body

The human brain uses about 20% of your body's total energy.

Fact #2340 · Human Body

The human brain continues developing into your mid‑twenties.

Fact #2476 · Human Body

You are slightly taller when you wake up than when you go to sleep.

Fact #2713 · Human Body

Your corneas receive no blood supply — they get oxygen directly from the air.

Fact #3275 · Human Body

Your stomach gets a new lining every three to four days because the acid would otherwise digest itself.

Fact #3491 · Human Body