The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
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
Enamel is hardest substance in the human body.
61
The average sperm cell swims at 8 inches per hour.
76
The human brain doesn't stop developing until about 25 years old.
102
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18