Enamel is hardest substance in the human body.
61
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
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190