30 Surprising Facts About Blood You Might Not Know

A Human body works as a joint force to keep the entire system running, running properly. But, as a force our body needs a general to guide and govern the entire system. A substance that brings oxygen to the entire body parts, removes wastes, fights germs and disease. Ring any bell? Yep! Blood it is. Without it, our body is like a car without fuel. There are many surprising facts about blood that you might not know. We provided those facts for you.


blood vessels laid end to end

An average human body has over 62,000 miles of blood vessels, if laid end to end it is approximately same as two and a half times of the total circumference of the earth. The Capillaries which enable the exchange of water and chemicals between blood and tissues, account for about the 90% of total length of blood vessels in the human body.


types of blood cellsImage source: wikimedia

The four main types of blood cells, namely A, B, AB and O, each of them have either positive or negative Rh factor. Blood group AB is the universal recipient, while O negative is the universal donor.

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human heart

During a full lifetime, a human heart can pump 1.2 to 1.7 million barrels of blood. The variation depends on the life expectancy of human.


blood cell

One microliter of human blood contains erythrocytes (red blood cells), leukocytes (white blood cells), thrombocytes (platelets) and plasma. By volume erythrocytes constitute about 45 percent of total blood, leukocytes and thrombocytes combine only for 0.7 percent and plasma is about 54.3 percent.


coconut water

While there are conceptions around, that coconut water can be taken intravenously as a substitute for blood plasma at times of emergency, but its high level of potassium can causes irresistible side effects through the whole body when taken. Several studies also prove that the coconut does not resemble to blood plasma, but closer to the fluid inside red blood cells.


gold in blood

Our body has about 0.2 milligrams of gold, and most of it is in our blood. However, it is not enough to make one wealthy.


blood in our body

The blood in our body accounts for approximately 7 percent of total body weight. An adult body, weighing 180 pounds (81 kg) contains 4.5 to 5.5 liters of blood.


blood preference mosquitoes

While there are many notions around that mosquitoes prefer a certain type of blood, type “O”, but many surveys and studies proved that mosquitoes does not have any sort of blood preference.


pregnancy stage

During pregnancy, women have as high as 50 percent more blood by week 20.



The first U.S president, George Washington was a firm believer in bloodletting, which was a standard medical practice for treating illness. He eventually died because of this.


newborn baby

A newborn baby has just about one cup of blood in his/her body.


donating blood

If a person started donating blood at age of 17 and donated after every 56 days until the age of 76, he/she would have donated a total of 48 gallons of blood.


need blood

People who have been badly injured in car accidents can need blood transfusions of 50 pints or more of red blood cells. While a severe burn victims can need 20 units of platelets during their treatment.


blood cells - how they used

After donating blood, body replaces those red blood cells within 3 to 4 weeks and it takes eight weeks to restore the iron content lost after donating.


after donating blood

After donating a pint of blood (a pint is equal to a pound) you lose a pound but without loosing your strength.


blood type O

The Bororo people in Brazil share same blood type “O” like the rest of native Americans.


running nose

During winters when our body gets cold, our nose receives more blood to keep it warm that causes the vessels to dilate and produce more mucus, which result running nose.


printer ink

HP printer ink is more expansive than the human blood. To compare, take an example of HP 45 black ink cartridge comes in for 30$ for 42 ml, which is $0.71 per ml. On the other hand 500ml blood cost 200$ pricing 0.40 per ml.


blood type

The blood is considered to be an indicator of personality in Japan. The Japanese version of Facebook has “blood type” dropdown for profiles.


human cornea

The human cornea does not have any blood supply it extracts oxygen directly from the air.

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blood-borne diseaseSource: haikudeck

A blood-borne disease is one that spread through the spreading of contaminated blood. For example, HIV, hepatitis B/C, and viral hemorrhagic fevers.


tiny bright dots

When looking into the bright blue sky, some of you may notice several tiny bright dots moving along squiggly lines. Those are mostly short- lived and moving fast for short distances in seemingly curvy paths. These are actually white blood cells moving in the capillaries in front of the retina of our eye. It is also known as the Blue field entoptic phenomenon or Scheerer’s phenomenon.


single blood cell

A single blood cell can make a complete circuit of the human body in 20 to 30 seconds.


mosquitoes sucking bloodImage source: lifedaily

There is an estimation that around 1.2 million mosquitoes, each sucking at once will completely drain the human body blood.



A Pus or simply pimple is formed from dead leukocytes (white blood cells) while resisting infection in the body.

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male female mosquitoes

The blood sucking creature also has their vegetarian community, male mosquitoes do not drink blood and female does.


blood centers

While there are mainly four blood group, but blood centers often run short of type O and B group.


blood donated

Just around three gallons of blood supports the entire nation’s blood needs for one minute (depends on the size of the nation).


Donated red blood cells

Donated red blood cells must be used before 42 days of collection. While Plasma can be frozen and used a year long.


blood cells under microscope

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In 1658 Dutch naturalist Jan Swammerdam was the first person to observe red blood cells under a microscope. Further, in 1842 French physician Alfred Donné discovered platelets. The following year, leukocytes were first observed and discovered by Gabriel Andral and William Addison.

Written by
Varun Kumar

I am a professional technology and business research analyst with more than a decade of experience in the field. My main areas of expertise include software technologies, business strategies, competitive analysis, and staying up-to-date with market trends.

I hold a Master's degree in computer science from GGSIPU University. If you'd like to learn more about my latest projects and insights, please don't hesitate to reach out to me via email at [email protected].

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