Could I live as a vampire by just drinking blood?

Thursday 26th August 2010
Submitted by cpearce1
ANON

Blood contains about 700 kcal/litre, so an average adult would need to drink around three litres to meet their energy requirements each day. Would this much blood also contain enough of the essential micronutrients though? Let’s consider vitamin C, as a worst-case example, because humans can’t manufacture it or store it. Average blood serum levels of vitamin C are around 5mg/litre and the World Health Organisation recommends at least 45mg per day. So you’d need to drink nine litres of blood to avoid getting scurvy, which would give you so many calories that you’d rapidly become overweight. If you dosed your victims with lemons before biting them however, you could raise their serum levels to 15mg/litre and 3 litres of blood would just be enough.

It’s been suggested that the high iron content of blood would lead to iron overload in vampires. But healthy humans can tolerate up to 45mg of iron a day and you’d need to drink at least 26 litres of blood to absorb that much. The real danger then? Salt. Human blood contains about 9g of salt per litre. Those 3 litres you’re drinking each day would give you around four and a half times your RDA, which would lead to dehydration and kidney failure if you didn’t also drink lots of water, and hypertension if you did.

GOT A QUESTION?

Scratching your head over a burning scientific conundrum? submit your question and we'll get our esteemed panel of experts to answer it for you.

 

What is the largest animal ever eaten by a Venus flytrap?
previous qanda Article
How does the power output of a traditional windmill compare to a modern wind turbine?
next qanda Article
Q&A Tabs

Phlegm is the mucous secretion of the respiratory passages. The cilia cells that line these passages are continually driving the phlegm upward to the throat, where it triggers the swallow reflex...

Viagra is the brand name for sildenafil citrate, a drug that was originally studied for use in patients with high blood pressure or heart disease. It works by blocking the action of an enzyme...

Our evolutionary ancestors lived with lots of toxic plants and we evolved a gene that makes the toxins in these plants taste bitter to discourage us from eating them. Children probably evolved a...

It’s not speed that’s the problem, but acceleration or deceleration. That’s what kills in a collision, for instance. Changes in speed are expressed in multiples of gravitational...

It depends on the temperature of the water. In cold water, the bacterial action that causes a body to bloat with gas may be so slowed that the body stays on the seabed. The skin will absorb water...

All female mammals have a clitoris, the sole purpose of which is to react to sexual stimulation, and presumably this stimulation has evolved to be pleasurable for most species. But establishing...

To create a sound, we have to set matter - whether it's a gas like air, a liquid or even a solid material - in regular motion, creating a wave of specific frequencies, which we hear as a sound of...

Mirrors don’t reverse left and right either – that’s just our interpretation of what happens. Your reflection in the mirror is actually reversed front to back – if you have...

Discovered by an American student named Gary Flandro in the mid-1960s, the slingshot manoeuvre usually involves spacecraft briefly 'coat-tailing' a planet orbiting the Sun, extracting some of the...

The ice disappears because the wind blows away water molecules that have evaporated or 'sublimed' from the ice, so the ice slowly shrinks in size. The molecules that escape are those with the...