Odd things, daily.
Porphyria is a very rare group of blood disorders that cause the sufferer’s gums to recede, giving the appearance of fangs. It also makes their skin boil and peel when exposed to direct sunlight. Sufferers of Porphyria are often treated with injections of blood. In short, this is the Vampire Disease.
In 1963, the Royal Society of Medicine published a paper suggesting Porphyria may have contributed to the vampire legend. Along with the appearance of fangs and aversion to sunlight, the paper explained that garlic contains a chemical that makes the condition worse, which may explain the origins of the Vampires-hate-garlic myth. The paper went on to explain that while the condition is treated with blood injections today, at one time victims may have attempted self-treatment by drinking blood.
Of course, there are some symptoms of Porphyria that clearly did not contribute to the Vampire legend, including the fact that sufferer’s faeces and urine comes out bright purple.
The disorder is caused when an important part of haemoglobin, called heme, is not produced properly. Although there is still a lot to learn about Porphyria, scientists have identified a mutation in the DNA of sufferers. Around 20% of all people have this mutation, and it can be triggered by alcohol, drugs, infections and even hormones such as estrogen.