Dolphin has spent years studying porphyrins, ring-shaped organic molecules that bind with metals. The most famous porphyrin rings are those found in the heme group - the red blood cell pigment responsible for catching and releasing oxygen. People with porphyria diseases have deformed hemes. There are seven main types of the disease, which range in rarity from one in 25,000 people to less than one in a million.

In sufferers, lone porphyrins build up in various tissues, especially the skin. They lie in wait like deadly little time-bombs that detonate when exposed to light by generating vicious free radicals which destroy the cells that house them. This violent reaction has led to porphryins’ nickname, “the pigments of death.” It might also explain vampires’ tendency to stray outdoors only at night, lest they burst into flames in the midday sun.

So were vampires really the blood-sucking undead of legend, or were they medically misunderstood in their time? Dr. Dolphin admits it’s only a theory but drinking blood would have allowed them to absorb more heme, which feeds back to ease up on excess porphyrin production. In fact, porphyria patients today get heme injections. Porphyrin build-up in teeth can make them appear reddish, possibly like bloody fangs. The disease is even associated with excess hair growth, especially on the forehead, possibly leading to the vampire’s trademark widow’s peak. The aversion to garlic may be explained by the fact that some chemicals in the plant, such as diallyl sulfone, increase the production of porphyrins in the body. Of course, he points out, that a wooden stake through the heart would kill anyone. As for the lack of a mirror image, Dolphin joked, “I’m a chemist, so I’ll leave that to the physicists.”