Your thumb is about the same size as your nose.
124
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
111
Enamel is hardest substance in the human body.
61
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Poor eyesight (myopia) is associated with higher IQ.
232