Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
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
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
Your heart will pump about 212 million liters in its lifetime.
26
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217