The logistics of devouring an entire human being (v1.13.2):

[architectap12]

So now i need a girlfriend who doesnt mind gaining twenty pounds for me lol loved this post and have been wondering about this for a very long time thank you

[CloningBacon]

TL;BSR ( Too long; But Still Read)

Very interesting. I'm surprised that anyone would devote so much time to get these numbers. A simplified explanation might be: Humans take a long time to digest and make you a lot heavier and will produce a pretty huge shit.

[Lumesa]

TL;BSR ( Too long; But Still Read)

Very interesting. I'm surprised that anyone would devote so much time to get these numbers. A simplified explanation might be: Humans take a long time to digest and make you a lot heavier and will produce a pretty huge shit.

My way's better.

[RedTornado]

Very interesting =o

[yummyyoungnorski]

Ok, now I'm actually curious and too lazy to look it up...I can understand why bone is indigestible but brain, blood, and lymph is also unnutritious and/or indigestible as well? Why is that? If so, then what is the purpose of eating this "junk food" from animals (for those people who actually eat these parts I mean)?

Blood is DEFINITELY digestible - in fact, blood pudding is a tradition in Australia (served on Qantas flights) and cow blood is drunk along with cow milk in Kenya. In both places, it yields extremely healthy quantities of dietary iron, and the extremely high iron content of the Kenyan diet is a major part of why Kenya produces many of the worlds best runners.

[Lumesa]

Ok, now I'm actually curious and too lazy to look it up...I can understand why bone is indigestible but brain, blood, and lymph is also unnutritious and/or indigestible as well? Why is that? If so, then what is the purpose of eating this "junk food" from animals (for those people who actually eat these parts I mean)?

Blood is DEFINITELY digestible - in fact, blood pudding is a tradition in Australia (served on Qantas flights) and cow blood is drunk along with cow milk in Kenya. In both places, it yields extremely healthy quantities of dietary iron, and the extremely high iron content of the Kenyan diet is a major part of why Kenya produces many of the worlds best runners.

For the sake of thoroughness, I'll add in the 4,950 calories that a human's entire blood supply bestows, but that's only about two days of caloric intake. It's very little compared to the rest of this hypothetical.

For the record, I never said it didn't have iron, either, nor that it wasn't nutritious. I didn't actually record anything regarding nutritional value outside of calories and weight gain. If you'd like to tabulate a measure of a human's total nutritional value, please, be my guest. I'd be happy to credit your glorious findings and add them to the original post.

[nipnaki]

Linear extrapolation

Pretty good for estimating weights of solids based on geometrical dimensions, pretty bad for estimating reaction rates for enzymes. Everything else seems to check out fairly well but I don't think that linearity is a good assumption to make here. First of all, you're trying to solublize what is functionally a convoluted sphere -- the inner layers can't be accessed by pepsin-catalyzed reactions before the outer layers are dissolved or mechanically perturbed. Unless you've got teeth in your stomach to uniformly distribute your prey and your stomach enzymes (which would be empirically hot, by the way), you're more likely looking at something like a power law. Compare it to heating a turkey in an oven versus rendering the turkey into a slurry and microwaving it or immersing heating elements. One of them is going to go a lot more quickly.

I suppose we could develop the dynamic system's approximate solution using differential equations if we so desired... We might want to use some Michaelis-Menton with each of the major enzymes though.

[Ignoring the poor pred's physiological concerns such as breathing, peristalsis (pumping losses on something this big could be significant), pH imbalance as a body fluid compartment fills with acid (those ions don't come out of thin air), nutrient transport with adequate bloodflow, etc.]

What you're looking at here is almost entirely concerns related to biology as we know it and the systems as they function in the real world. While, yes, that is the basis for the number crunch up there, I'm not daft enough to think it's not still impossible. Again, this was never the actual point of this post. I didn't do full nutritional information, and I sure as hell didn't try to apply guts as-is. This is all a thought experiment under the assumption that the human stomach can, in fact, handle digesting a human. Lack of elasticity alone makes this prohibitive in the real world, much less going into the specifics of acid production, the production of neutralizing mucus to protect your organs, the ability of the muscle to contract and churn, etc. You've gone afield with this one, but if you'd like to crunch the numbers that'd be required for the digestive system to actually be able to handle this, I'd be more than happy to post them for all to see in credit to your glory. It's just not what I was trying to do, and it's not what I'm gonna devote time to.

That said, if you can work out the effects of acids on digestion time, I can apply them as well. Extrapolation is pretty magical in that it can be altered with additional data.

Oh the things this community does to me.
OK: TL;DR: my math says you're going to need more time.

Making several very generous assumptions about the boundary properties of this mass transfer problem, I come up with a rough estimate of 204 hours that are necessary to "completely" solublize a sphere of collagen of the given mass and volume within the stomach. These numbers are humorously hard to look up to tolerances closer than an order of magnitude. To simplify I made the following additional assumptions: The stomach is arbitrarily large and filled with a homogenous fluid which always has a protein concentration arbitrarily close to zero. There are no chemical reactions occurring to add protein. There is no protein being added from the outside. The concentration of protein at the liquid interface between the sphere and the fluid equals the concentration of protein in the solid sphere (This one's a doozy, and would likely require Michaelis-Menton to resolve). The sphere is homogeneous. The sphere may be assumed to be in a mass transfer pseudo-steady state for differentiation purposes.

Basically to dissolve a substance under these conditions the (long and likely boring to many) derivation resolves into:

Code: Select all

t=sqrt((R0*2*rho)/(Dbs*Cb))

Where:
t is the time required to reduce the sphere's radius to zero
R0 is the initial radius (cuberoot((3/(4*pi))66400 cm^3))
rho is body density (934 g / L)
Dbs is diffusivity of collagen in water (~10^-7 cm^2/s)
Cb is the (ugh) density of collagen at the interface (~1g/L)
[again, I must stress that in the absence of mechanical digestion being performed on the prey, this figure is almost certainly too large]

The enzymatic part of digestion largely occurs in the intestines, and probably follows something close to Michaelis-Menton. Pepsin has an approximate maximum reaction rate (note: this is defined as a saturated solution) of Vmax = 150 ug/(mL*sec). A dumb unit analysis would tell me that in 99 hours pepsin in a CONSTANTLY SATURATED SOLUTION (read: basically just the duodenum) will have performed an enzymatic operations on 7571 g of protein. This is more than we estimate there to be in the human body so good! This is not our rate-limiting step!

(to be continued. Later. Maybe.)

[Lumesa]

Oh the things this community does to me.
OK: TL;DR: my math says you're going to need more time.

Making several very generous assumptions about the boundary properties of this mass transfer problem, I come up with a rough estimate of 204 hours that are necessary to "completely" solublize a sphere of collagen of the given mass and volume within the stomach. These numbers are humorously hard to look up to tolerances closer than an order of magnitude. To simplify I made the following additional assumptions: The stomach is arbitrarily large and filled with a homogenous fluid which always has a protein concentration arbitrarily close to zero. There are no chemical reactions occurring to add protein. There is no protein being added from the outside. The concentration of protein at the liquid interface between the sphere and the fluid equals the concentration of protein in the solid sphere (This one's a doozy, and would likely require Michaelis-Menton to resolve). The sphere is homogeneous. The sphere may be assumed to be in a mass transfer pseudo-steady state for differentiation purposes.

Basically to dissolve a substance under these conditions the (long and likely boring to many) derivation resolves into:

Code: Select all

t=sqrt((R0*2*rho)/(Dbs*Cb))

Where:
t is the time required to reduce the sphere's radius to zero
R0 is the initial radius (cuberoot((3/(4*pi))66400 cm^3))
rho is body density (934 g / L)
Dbs is diffusivity of collagen in water (~10^-7 cm^2/s)
Cb is the (ugh) density of collagen at the interface (~1g/L)
[again, I must stress that in the absence of mechanical digestion being performed on the prey, this figure is almost certainly too large]

The enzymatic part of digestion largely occurs in the intestines, and probably follows something close to Michaelis-Menton. Pepsin has an approximate maximum reaction rate (note: this is defined as a saturated solution) of Vmax = 150 ug/(mL*sec). A dumb unit analysis would tell me that in 99 hours pepsin in a CONSTANTLY SATURATED SOLUTION (read: basically just the duodenum) will have performed an enzymatic operations on 7571 g of protein. This is more than we estimate there to be in the human body so good! This is not our rate-limiting step!

(to be continued. Later. Maybe.)

I'll be goddamned if you didn't make more work for me. Now I have to not only apply this new math, but I have to find several mean amounts of various substances in the human body and their solubilities, since homogeneous collagen just won't cut it for the math involved. I'll also need to hunt down the actual makeup of the applied stomach fluid per volume, assuming, same as you have, an arbitrarily large stomach. Then, for the sake of thoroughness, I'm gonna have to account for constant mechanical digestion. Essentially, you've given me a base to work from, but there are factors that'll need working through on this. Some homogeneous things need to be accounted for as different materials (the collagen sphere assumed as the human-substitute, the "fluid" that'd be made up of pepsin, HCl, and gastric lipase).

Naturally, this functions under the assumption of adequate mucin production, pancreatic activity, and small-intestinal hormone production for the predator to be safe from the detrimental effects of this. And, of course, their other systems would be able to "handle it." It really wouldn't be any fun at all without those assumptions, obviously.

I'll work on it when I can. Got five solid days of drawing commissions and home improvement ahead of me, so I'll get at it after that.

Math is kinda fun, yo.

[DethXev]

Math is kinda fun, yo.

Word. Chemistry as well. I rather like this thread. Wish they would've given us this topic to test these theories in a lab back when I was in college, lol.

[Lumesa]

Math is kinda fun, yo.

Word. Chemistry as well. I rather like this thread. Wish they would've given us this topic to test these theories in a lab back when I was in college, lol.

Actually, one of the reasons I haven't finished this is due to a lack of readily-available materials regarding the math I need. Because of this fact, however, I'm actually working with someone to set up an experiment using the involved chemicals. With the data gleaned from that, this will be able to be made more accurate.

[Artemis]

This is interesting to say the least. It's kind of fun to imagine a hyper realistic digestion period for someone in real life.

it's not so fun imagining losing my figure, but it's neat to know anyway!~

[nipnaki]

Math is kinda fun, yo.

Word. Chemistry as well. I rather like this thread. Wish they would've given us this topic to test these theories in a lab back when I was in college, lol.

Actually, one of the reasons I haven't finished this is due to a lack of readily-available materials regarding the math I need. Because of this fact, however, I'm actually working with someone to set up an experiment using the involved chemicals. With the data gleaned from that, this will be able to be made more accurate.

Nice. I would suggest doing ex vivo stuff trying to emulate unbroken skin and other epithelial tissues, but that would probably be difficult to do experimentally. Are you thinking of doing this with pre-killed feeder rats? Simulating mechanical digestion might be hard, and the timepoints of infusing different reagents might be hard to specify. Like, is it appropriate to just start adding bile after a few hours or do you wait until everything's basically chyme? Then you come up against the question of what the minimum number of enzymes you can use are in order to get away with good data. Mustn't forget temperature effects either. Good luck! Sounds like... a way to spend your holidays.

[Artemis]

Y'know, after thinking about it I realized I would really, really like to know the nutritional value of a human. I would also like to know how much weight one might gain if they did a bare minimum exercise routine, say 15 minutes of jogging and 15 minutes of stretching exercises every day.

[Eupeptic]

I approve of this post. :D

You've thought about this a lot. Just don't ever eat anybody, OK? This post might be used at your trial, in that case. :)

Eupeptic

[Filan]

Build a shrink gun and make the swallowing part much easier.

[MelancholyClownD]

very interesting! XP
What would be more nutritious, A male or female prey? :O

[TransDimetroPolitan]

As you're clearly proven yourself already. I had a semi related question. I have.. a thing for characters gaining weight solely on their stomach, specially after vore. I wondered how much weight say a sphere of pudgeiness at different feet radius/diameter (the rule of description me and my partner generally use in rps) would add to a characters weight. My own attempts at working this out have been kinda pityful..

[Lumesa]

As you're clearly proven yourself already. I had a semi related question. I have.. a thing for characters gaining weight solely on their stomach, specially after vore. I wondered how much weight say a sphere of pudgeiness at different feet radius/diameter (the rule of description me and my partner generally use in rps) would add to a characters weight. My own attempts at working this out have been kinda pityful..

You can apply the same percentages by weight that I've already used! Fat is adipose tissue, and if it's just gained in one spot doesn't really alter the amount of fat transfer, so it'd be the exact same formula. I admit freely, however, that the time employed in digestion in my workings may be a few days too short. This is due almost wholly to a lack of data on the action of digestive juices on the prey, so I'm missing variables to complete the time equation. Time, of course, has a possibility of also altering the end-weight (though it's likely possible to maintain a no-loss situation if you still consume roughly 2000 calories daily after the first 4-or-so days).

The short of it is: you can get roughly accurate results in this situation the same way as I did. As for actually measuring the diameter of the resulting belly after weight gain, one gram of fat (the weight you'd gain) is roughly 1.1 mL, so just multiply from there to get a volumetric sphere equal to the amount of fat you'd gain and apply it only to the belly!

[Redatheart]

Reading this has been amazing (who knew math could be so hot?). So amazing, I did some calculations of my own, with a particular question in mind...

It has been established that it takes 33.1 days to fully process 1 person

If someone is eating a 2500 calorie diet over the course of 33.1 days, they'd consume a total of 82,750 calories
similarly, if someone is a bit more active (3,500 calorie diet) over 33.1days they'd eat 115,850 calories
1 person = 139,725 calories
so by eating one person, and living on a standard 2500 calorie diet, you'd feed yourself for 55.89 days
living on a 3500 calorie diet, you'd feed yourself for 39.92 days off 1 person. And hey, carrying 100 some odd pounds around all day would be a bit of a workout
So if you eat 1person every ~40 days, you'd have to eat 9 people a year (and plenty of vegetables and fruit along the way, assuming one person dosn't have all the vitamins and minerals you need for 33.1 days)

but wait

Who here eats just one meal until they expel it? There's lunch and dinner for a reason, and it's not just to keep ourselves feeling full

So how many people would you have to eat until your first meal leaves you?
Well, 1 normal meal (let's say breakfast) takes 47 or so hours to leave us
1 person takes 33.1 days
while 1 normal meal takes a full tour, a person eats 5-6 (5.8 exactly) other meals in the meantime
If that is applied to eating a human whole, a person would eat another person every 5.7 days (5.8 people in total until the first one is expelled)
Over the course of a year, one person would eat roughly 64 people

What kind of birth rate would sustain/slightly grow a population, in which one person eats that many people?

[Maenethal]

India?