Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Your heart will pump about 212 million liters in its lifetime.
26
The average person's skin weighs twice as much as their brain.
131
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
The human brain has the capacity to store everything that you experience.
4k
Your body is creating and killing about 2.4 million red blood cells per second.
17