The blood vessels in the adult human body have a length of about 100,000 km (or ~60,000 miles).

Humans blink about 25,000 times a day on average.

On an average, a woman blinks even more than a man, almost twice as often.

Men are far more colour blind than women, almost 10 times as much.

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Human bones don’t last long; their tissue is continually destroyed and replaced bit by bit with the result that means that the whole skeleton is renewed about every seven years.

There are about 100,000 hairs on the average human head usually has more than 100,000 hairs. People with very fine hair have even more, namely up to 200,000 hairs.

Human lungs have a total surface area about the size of a tennis court. They contain about 300 billion capillaries, their combined length several thousand km long.

The most active muscles are the eye muscles. They contract more about 100,000 times during a 24- hour day.

The eye muscles are also the fastest ones with contraction times of less 1/100^th of a second.

For functioning properly, the human brain needs more than 25% of the oxygen used by the whole body.

The human brain consists of about 80% water and only 20% other matter.

The brain works better after aerobic exercise (like brisk walking, jogging, cycling,

 swimming etc.).  Such activities can improve the brain structure by increasing connections between neurons in part of the brain.

There are billions of living organism on your skin, more than all people in the world.

About 10% of all people are left-handed. However, the proportion of left hand participants in NASA’s Apollo Space Program was about 1 in 4, that is 25%.

A scientific survey in a hospital Boston has come to the surprising conclusion, people with natural blond hair are far more likely to be left-handed than people with dark or red hair.

Science has also found that on average right hand people live about nine years longer than left hand people.

Fear of spiders is unjustified in most cases. It is been found that the likelihood is greater to get killed by a champagne cork than by a poisonous spider.

Sharks are dangerous if attacking. But did you know that it is more likely to be by coconuts than shark?