Code/Switch – Vampire Diets Suck

Hi, my name is James and welcome to Code/Switch, today I want to talk about blood. Blood, we all have it, we all need it, but do you know who needs it twice as much? Vampires. That’s a lie, I’m sorry. In Pathfinder vampires are immune to bleeding due to their undead template, but, they still like blood! Seriously, in Pathfinder it makes no sense why vampires would want blood besides a little energy boost, what a thing to terrorize small hamlets over. Thankfully Paizo literally vomits vampire subtypes to play as and be terrorized by. For today’s Code/Switch I want to highlight a vampire’s all-blood diet, and why it’s bad nutritionally.


I know what you’re thinking “But James, plenty of creatures drink blood and they’re fine!”, you’re wrong, they suck. Hematophagy (the practice of eating blood) actually isn’t rare among creatures, with such animals being categorized into obligate (needs for life) and facultative (needs along with other food). Our collective consciousness of blood suckers tends to make us remember the obligate hematophagous more often than facultative, the obligate group including; vampire bats, bed bugs, leeches, and lamprey. Creatures who are facultatively hematophagous include; Vampire Finches, Mosquitos, and Oxpeckers.  Oh, and humans I guess. Man, I didn’t think vampire bats were scary until I saw them run.

While vampires are themselves supernatural, they’re an extension of the human imagination, so we’ll be seeing how a human would do as an obligate blood-drinker and use that to fill in how vampires are cheating the system. Sadly, I couldn’t find any accurate figures for human blood, just this hopefully joke entry on this website where people enter foods to track intake. This put me at a loss for estimating the nutrition in blood until I remember that pigs are basically humans.

She means humans are pigs, not describing the events of Animal Farm by George Orwell.

Now, to compound that problem, its hard to find nutritional info for raw blood. When blood is consumed in foods we humans ate, we usually congeal it into a gel or stuff it into a sausage casing, so I’m using relatively suspect data, but it’s the best I could find. We’re also going to just assume blood is as dense as water, it’s not, but it’s pretty close, so that’ll make our math easier. On average, an adult human has 1.2-1.5 gallons of blood, converted to ounces, its ~172oz of blood. Using that figure and our nutritional info, we’d see a humans blood total 3,912 calories, 3/4ths an ounce of sodium, 894 grams of protein, over 100% of your vitamin A recommendation and almost 17 times your daily requirement of iron.


While this seems nutritious, as a sole food source, blood would be garbage. You’d need to drink a whole person daily to meet your calorie needs if you were a young, strapping, active liquid cannibal. You’d also probably suffer iron poisoning, causing bloody stool and vomit. You’d also be thirsty, SO THIRSTY. You’re taking in 9 times your recommended sodium intake and your body has to process a glut of protein and iron, which also takes water to do. If somehow that didn’t stop this all blood diet, you’d suffer scurvy, hypokalemia (too little potassium) and hypocalcemia (low calcium) so your blood vessels would rupture, your bones would become brittle, and you’d suffer seizures as your body becomes unable to transmit electrical signals correctly. Oh, then you die.


In conclusion, vampires have to be much less human than we give them credit for. Even being undead, you’d think their cells would functional in similar ways if they have a human base. I just have to throw up my hands and accept the wisdom imparted by Max Landis’s dad to him about rules for killing a vampire; that they’d made up, and you can do whatever you want. Cheeky language.


Find me and the rest of the KD crew at our Discord!

James Ballod

James blossomed into geekdom like a piranha plant in the crack of a sidewalk. Watered by the muscle-brained lore of Warhammer 40,000 and nurtured in the rough bosom of World of Warcraft, tabletop RPGs came late in life to James. The rich lore and real-world influences in games like Pathfinder inspire James to explore them from every angle. When not being an annoying anime-fanboy he can be found discussing the history of various cuisines and over-analyzing real world influences in works of fiction.

The Road to PF2 with Logan Bonner and Jason Bulmahn