Enamel is hardest substance in the human body.
61
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Poor eyesight (myopia) is associated with higher IQ.
232
The human brain doesn't stop developing until about 25 years old.
102
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92