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
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
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127