Yawns are more contagious among people with closer relationships.
163
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Enamel is hardest substance in the human body.
61
The human body contains over a billion miles of DNA.
147
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
The average person's skin weighs twice as much as their brain.
131
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190