#everheartless

In today's installment of Safety Rat's adventures, he has endorsed the destruction (and subsequent explosion) of the boiler in the basement!

He has sustained hearing damage from said explosion!

Empiresblr: Angst, angst, angst >:)

Mr. Smajor: You want angst, you said? :)

Empiresblr:

Mr. Smajor: I can give you angst. :)

Mr. Smajor: *Elsa arc, "I don't want to hurt you," the disaster at Gem's, self-imposed exile, maybe for centuries*

Empiresblr: ...wait, that's not-

Mr. Smajor: Oh, and one more thing...

(Hear me out. My biology degree is coming in use for something.)

700 Calories per liter

That's the hypothetical nutritional value of human blood (assuming you can digest it. We aren't meant to drink blood and don't have the equipment for it. This has been your don't drink blood PSA).

Assuming a human-like metabolism, that's nearly 3 liters of blood a day to support a 2,000 Calorie diet (and about 4 fully-drained humans per week). This seems a bit high for even a fairly gory vampire interpretation.

Therefore, let's consider if a vampire metabolism resembled an ectothermic (cold-blooded) animal's. Why does this matter, you ask? Well, ectotherms famously have lower metabolisms than endotherms (warm-blooded).

Here's a nifty graph I found to illustrate. (Link: https://royalsocietypublishing.org/doi/10.1098/rstb.2019.0146)

Yellow highlighted line is ectotherms (cold-blooded)

Blue highlighted line is endotherms (warm-blooded)

TL;DR, if vampires were ectotherms, they would not need to eat as much.

According to dodgy first page Google results, humans need very roughly 30 Cal per kg a day whereas a larger reptile (I used alligator research, link: https://pubmed.ncbi.nlm.nih.gov/2366112/, for my estimates here) need less than 10 Cal per kg a day.

Using the low end of the study linked above to hopefully counteract the fact it references juvenile, GROWING alligators instead of adults, 5.7/Cal a day, we get a nutritional requirement of about 456 Cal per day for a vampire weighing 80 kg (about 180lbs).

Some more dodgy Googling even popped up numbers as low as 3 Cal/kg a day for large reptiles like alligators, equating to about 240 Cal per day for the same vampire.

Now, let's talk blood.

Bringing back that 700 Cal/L number from earlier and that your standard whole blood donation is 500mL, that's about 350 Calories per standard blood donation. Depending on the activity and weight of your vampire, it seems like 1-2 standard blood donations per day would suffice.

Translated into whole humans (for your more murderous interpretations), that's less than one human a week.

(For the math, 0.912 humans for the 456 Cal/day number and 0.48 humans for the 240 Cal/day number.)

We're talking around 2-4 humans a month.

So, I finally have a finished product to show the internet!

For context, I read Poker's The Snow King on AO3, LOVED it, and desperately wanted a copy. The logical solution? Learn how to bind books, obviously.