10 Amazing Things You Didn’t Know About Blood



Blood is one of the most important parts of our bodies, transporting vital oxygen, vitamins and minerals around the various organs. The fact it is so significant, along with the fact that it has a striking appearance due to its strong red color, means that it is also rather dramatic. In fact, blood is often used in movies and television shows to signify injury or harm. Despite the important role it plays though, there are plenty of things that people don’t know about it.

Blood Is Never Blue

Despite the common belief that blood is blue when it isn’t oxygenated, blood is never that color. The red liquid simply looks blue under the skin because of the way that blood interacts with light in veins.

But Other Creatures Bleed In A Variety Of Colors

Although humans only have red blood, other animals on the planet have a wide range of different colored blood. This includes some crustaceans having blue blood while a particular species of leech bleeds a green liquid.

Experts Once Believed The Heart Burnt Blood

Before the circulatory system was fully understood, many medical experts believed that the heart didn’t pump blood around the body but rather burnt it to create energy. Luckily, William Harvey was able to detail the full working of the veins, arteries and heart in 1628.

The British Royal Family Were Hemophiliacs

Until very recently, members of the British royal family suffered from a very rare affliction known as hemophilia B. This effectively prevented their blood from clotting properly, meaning any would or injury could be fatal as the blood would not stop flowing. The condition has affected them since a random mutation occurred in Queen Victoria’s genes.

Other Animals Have Blood Types

While humans have three major blood types, A, B and O, they aren’t exclusive to our species. Many other animals have their own unique types, including dogs which have more than a dozen different forms.

Ancient Romans Drank The Blood Of Gladiators

Many ancient civilizations believed that blood had curative properties and could treat a variety of problems. As transfusions had not yet been invented, most people would simply drink blood taken from an animal or person. Some Romans would even wait in the wings to drink the blood of gladiators who had been killed in battle.

A Mismatched Transfusion Can Be Deadly

While some blood types aren’t important for transfusions, some can vital to get right. Otherwise they can cause dangerous reactions as the molecules begin to clot and the body’s immune system begins to attack the blood as it sees it as an outside threat.

Plays Often Used Animal Blood In Performances

Before realistic and genuine looking fake blood could be produced, actors would simply use animal blood to simulate human blood in their performances. Before a play was set to begin, someone would simply go to a slaughterhouse to collect enough of the liquid.

Doctors Experimented With Animal To Human Transfusions

Before blood was fully understood by scientists and medical professionals, some doctors experimented with giving their patients transfusions directly from animals. These didn’t go as planned and most people suffered from instant reactions that included vomiting and kidney failure.

Brain Freeze Is Caused By Blood

The most commonly accepted explanation for brain freeze has to do with the arteries leading to the brain. The cold temperatures reacts with the blood, causing the arteries to dilate very quickly, which causes the intense pain in the mouth and head.