Yawns are more contagious among people with closer relationships.
163
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average sperm cell swims at 8 inches per hour.
76
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The average person's skin weighs twice as much as their brain.
131