The half-life of caffeine in the human body is about 5 to 6 hours.

The average adult human has 32 teeth.

Fact #152 · Human Body

Less than 1% of people have heterochromia, where eyes are different colors.

Fact #2869 · Human Body

Roughly 60% of your body weight is water.

Fact #2796 · Human Body

A human brain generates enough electrical activity to be measured outside the skull.

Fact #2500 · Human Body

The human heart beats about 100,000 times per day and around 2.5 billion times in a lifetime.

Fact #3504 · Human Body

Teeth are the only part of the body that cannot heal themselves.

Fact #3279 · Human Body

The human skeleton renews itself over time.

Fact #133 · Human Body

The pacemaker regulates irregular heartbeats.

Fact #1581 · Human Body