10 things you don't know about your body:

1) Your mouth produces 1 litre (1.8 pints) of saliva a day.

2) The human head contains 22 bones. More on the head and brains.

3) Men loose about 40 hairs a day. Women loose about 70 hairs a day.

4) The muscle that lets your eye blink is the fastest muscle in your body.

5) Fingernails grow nearly 4 times faster than toenails.

6) Every person has a unique tongue print.

7) We actually do not see with our eyes - we see with our brains. The eyes basically are the cameras of the brain. One-quarter of the brain is used to control the eyes.

8) If all your DNA is stretched out, it would reach to the moon 6,000 times.

9) On average a hiccup lasts 5 minutes.

10) If the amount of water in your body is reduced by just 1%, you'll feel thirsty.