Enamel is hardest substance in the human body.
61
Every year your body replaces 98% of your atoms.
119
The average sperm cell swims at 8 inches per hour.
76
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Your heart will pump about 212 million liters in its lifetime.
26
