For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
It takes about 20 seconds for a red blood cell to circle the whole body.
102
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
Your heart will pump about 212 million liters in its lifetime.
26
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111