It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Enamel is hardest substance in the human body.
61
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Yawns are more contagious among people with closer relationships.
163
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515