Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Chewing gum boosts your brain power.
285
Yawns are more contagious among people with closer relationships.
163
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46