The human brain doesn't stop developing until about 25 years old.
102
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
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
The human body contains over a billion miles of DNA.
147
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
One human hair can support 3 ounces.
191