Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The average sperm cell swims at 8 inches per hour.
76
One human hair can support 3 ounces.
191
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127