Yawns are more contagious among people with closer relationships.
163
Your heart will pump about 212 million liters in its lifetime.
26
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Your thumb is about the same size as your nose.
124
The human brain doesn't stop developing until about 25 years old.
102
The human body contains over a billion miles of DNA.
147
Your body is creating and killing about 2.4 million red blood cells per second.
17
If you are cold you are more likely to be hungry because you use energy to keep warm.
143