It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The average sperm cell swims at 8 inches per hour.
76
The average person's skin weighs twice as much as their brain.
131
The human brain doesn't stop developing until about 25 years old.
102
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Yawns are more contagious among people with closer relationships.
163