A bitten lip, the sweet tang of ions, the rich, slightly thickened liquid. Must that be how Dracula daydreams? Vampire lore has morphed and taken over the modern fiction scape: from Buffy to Twilight to True Blood. I remain partly enthralled (well, the stuff tastes mysteriously interesting, reminiscent of canned water) and partly disgusted (could a solely blood-based diet really settle well digestively?). But the question remains — is there such thing as a primal thirst for blood? Is this notion completely fictionalized or could there be an explanation for this all-consuming craving for the taboo metallic juice? In short: is there such thing as a blood addiction?

Here’s how Dracula could have happened:

1. Nasty combination of porphyria, pellagra, and pica

Porphyria

Applicable symptoms: light sensitivity, blistering and rashes when exposed to sunlight, mental disturbances, personality changes

This realm of disorders occur when heme in the blood’s hemoglobin isn’t properly produced. Porphyria is largely hereditary, though drugs, alcohol and infection can trigger onset.

Pellagra

Applicable symptoms: sensitivity to sunlight, insomnia, aggression, psycho-motor and emotional disturbances, eventual dementia

This systemic nutritional wasting disease stems from a chronic vitamin B3 deficiency, sufferers often afflicted with thickened, rough skin. Earliest reports began in the 1730s and are commonly found among poor populations with an excess of corn in their diet. This can develop after alcoholism.

Pica

Applicable symptoms: non-food substance craving

This compulsive eating of such things as dirt, metal, chalk, cigarette butts, hair (and everything else under the sun that isn’t food), is called pica, categorized as a mental disorder and eating disorder. This strange-sounding affliction has been noted across cultural groups, age and time periods in history. Some reports sway pica to be rooted as a nutrient (such as iron) deficiency problem, while other researchers believe it has psychological roots, like that of obsessive-compulsive disorder.

2. Rabies

Applicable symptoms: restlessness, hypersensitivity to stimuli, insomnia, retracted lips, mental disturbance

This one’s a bit difficult for me, as the idea of a foaming-at-the-mouth vampire is more than a little off-putting. Still, a viral disease causing brain inflammation and central nervous system infection from animal bites would explain the vampiric crazed tendencies, nocturnal habits and bared teeth.

So, our creepy vampires of yesteryear and sexy ones of today likely have psychiatric problems, alcoholism and genetic disorders in common. Does this induce grimaces or sympathy for the strange, odd and misunderstood creatures — bad boy/girl addicts — that they are? Or, could some different affliction entirely be at play?