Possible to build an artificial digestive tract?

No, no. He’s not talking about the action of the intestinal tube, he’s describing how his concept of an artificial intestine would work. He seeks to save energy by having it rely on gravity (which means it wouldn’t work when you were asleep), rather than actively pushed through, the way intestines actually work. Your explanation was excellent, by the way, but I think the OP was aware of the points you raise.

Heh. If that is what passes for a “working” jetpack to you, I can see your credulity bar is set very low. Without hijacking this thread any further, what is the longest flight any of those “Bell Labs-style” devices has ever flown? 20 seconds? A minute? That makes it at best a novelty, a toy hardly comparable to hovercraft or submarines.

And also, I might add, complexity.

So, in your esteemed opinion, is it technologically feasible to mimic peristaltic action in a flexible tube device?

Yes, so I proposed a device that requires no surgery to deploy. Are you suggesting that any foreign device put in the gut will destroy a healthy digestive tract, thereby requiring surgery?

If I’ve offended you, then I apologize. Am I being insistent? I’m just asking questions here in the question-asking forum, and frankly, some of the objections seem to border on the wrong side of the fighting-ignorance battle. What specifically did I say that you find factually incorrect?

Do you deny it is a working jetpack? There is video of a guy flying on the same website, if you don’t believe me. To answer your question, the current prototype is 33 seconds (300 feet), with an 8 minute model planned. In keeping with the spirit of GQ, I will let it go at that.

A jetpack that can only fly 33 seconds is not working in my book. As for what they have planned, pardon me if I believe it when I see it.

Despite the possibilities here for a really good train wreck, I think you need to back down. People are poking fun at you for the good and sufficient reason that you don’t seem to have the slightest clue about how the digestive track works, or how digestion works, or any how any subject related to your idea works. You don’t even understand enough about the subjects to form a coherent OP, especially if you think calories and nutrients are separate things.

What you’re suggesting is an artificial tapeworm. Think of it that way. You want to duplicate an entire living organism, put it inside a healthy digestive tract, and keep it from interfering with the workings of that digestive tract. You’re not asking questions; you’re insisting that your magic is science and attacking all who disagree.

It’s magic, though. It’s not even very good magic. One f&sf writer came up with a better solution. He had magic food that tasted and satisfied like food as it went down but simply disappeared when it hit the stomach. And I still say that we’re closer to coming up with magic food than with your device.

I think sales of Beano would also increase dramatically, as the resident bacterial flora of the large intestine learn to feast on previously unavailable foodstuffs.

Yes, that’s exactly what I’m suggesting. “Artificial tapeworm” would’ve worked better in the thread title.

As for attacking others, that isn’t my intent. I disagree with your statement that I am not asking questions. Perhaps you are reading something into my posts that isn’t there?

I also disagree that it’s “magic”. Many of the objections you and other posters have given could be applied to other technologies, such as artificial hearts, gastric bypass surgery, or lap band surgery. I would not have presumed to use the label “magic” with those ideas, even years ago before they were invented.

Calories aren’t a constituent of food. They are the result of a process. Consider protein. Protein can be used for metabolism, but it can also be used to make new skin and hair. Sometimes the calories are burned and sometimes they’re not. The body isn’t a simple machine and calories are not separate from nutrition.

Instead of messing with the incredibly complex digestive/metabolism system, you’d be better off working on the problem of satiety. If eating a cup of food gave you the same feelings of fullness and satisfaction of a seven course gourmet meal, then you’d really have something.

You might be interested in Vaucanson’s pooping duck from 1739, although that one was actually a bit of a fake.

Actually, I think they are. Otherwise, why does consuming 3500 fewer calories reduce a pound of fat?

Perhaps so, but some people like to eat… maybe they prefer to enjoy the seven course gourmet meal instead of a cup of food.

Calories are a property of food. Not a constituent. Everything you take out has a caloric value associated with it. The job of your artificial tapeworm is to take out “empty” calories; a sort of a strictly-enforced diet. That’s a surprisingly difficult thing to do, since you have to do it on the molecular level. The large groups of molecules that accept or reject materials from the intestines into the blood stream do so by actively identifying the molecules in our food that it interacts with. We’re talking about something we’re hundreds of years from being able to duplicate, at the very least.

I think what daffyduck meant is that you have referred to calories as if they were a separable component of food - they’re not - they’re an * intrinsic property*.

Sure, but the problem still remains: how do you get partially digested manner to progress through this artificial intestine? Gravity is insuffient to prevent blockage, as anyone sitting on the toliet in a state of constipation is aware. Even if the device is straight up and down (in the standing position) you’re going to have to force matter to advance.

Sure, it’s done all the time with food service equipment; using peristaltic action on a flexible tube prevents contamination of the fluid. (Take a look at the chilled coffee machines sometime.) But to make it implantible and connect it up to the intestines? Nope.

I’m unclear as to how you intend to implant this in the intestines without surgery, but regardless, no, you don’t want to be putting foreign objects in your digestive tract. It is (when not fed a diet of high fat products or spicy foods) a fine-tuned machine that doesn’t react well to anything it can’t break down, and any scheme involving cutting into the intestine is highly suspect. Cutting into any major organ carries the risk of infection, of course, but surgery on the intestinal tract virtually guarantees an infection that has to be fought off. I’ll leave it to Qadgop to offer amusing anecdotes of the various things inmates have done to their intestines, but needless to say, this is not an organ one performs routine elective surgery upon.

I’m not offended. (I am a little cranky, but that’s entirely seperate from this.) However, it’s one thing to propose an idea (“I’d like to improve my vision, so I was thinking of drilling out my pupils. What say you?”) but another to dismiss valid, factually-based difficulties and objections with a wave of the hand. “I’m sure someone can figure it out; after all, how hard could it be?” is the bane of existence for engineers and scientists. It’s not just a matter of “figuring it out”; we often lack the basic understanding, technical capability, and experience to be able to fulfill the dreams of would-be inventors and science fiction writers.

It’s one thing to propose a high level concept, and quite another to make all of the details work. As an example, cellular communications are “easy” in concept; you just have transmitters networked together and routing calls from and to mobile handsets. What could be easier? The details, however, are fiendishly difficult, a challenge that is totally unappreciated by Paris Hilton-wannabes who babble on through a movie while I’m trying to catch the fine scientific detail of Armageddon.

You’ve tossed out an idea, some of the most erudite people in this forum have responded with various challenges, difficulties, and references, and your immediate stance is one of staunch defense of your thesis rather than a desire to understand the challenges. There’s value in contesting “the experts”, but such challenges need to have basis in the fundaments of the topic at hand. You need to read up on and understand how the GI system works before assuming that with enough pale guys in white lab coats on the job we can somehow make it go.

Stranger

Exactly - and this is where much of the research is focused. “Our” knowledge of the neurochemistry of appetite and satiety is growing on an almost daily basis. In the next 10 to 15 years, there will be a slew of drugs available based on the relevant molecules. Until then, efforts to succeed at satiety fulfillment will have to continue to rely on things like gastroplasty.

By the way, with respect to the OP, there used to be an operation performed called jejuno-ileal bypass (and it may still be being performed in some places). The idea was, similar to that proposed in the OP, to alter the digestive tract so as to prevent absorption of much of the ingested food (and hence calories). Again, I bring this up because it resembles, somewhat, the idea put forth in the OP here.

Take a look at the link (starting about half of the way down) and also let me summarize: the medical complications of such surgery (let alone all the surgical problems) include things like kidney failure, severe arthritis, bone disease, malabsorption, and liver disease :eek: . And that’s what happens even with a relatively modest and straightforward attempt to fool the small bowel. IMHO, it’s going to be a long time, indeed, before we create an “artificial digestive tract”.

Now this is an interesting idea; would it be possible to selectively breed a subspecies of tapeworm that had the effect of consuming calories without inflicting damage to the host? Aren’t most tapeworm infections asymptomatic anyway?

except for the big, nasty “gusanera” belly, you mean.

I read a sci-fi story back in the 70’s about a guy at a space station who was pissed off at the fact that he couldn’t get a decent glass of milk there. He got many of the rest of the scientists at the space station to help him, and they built an artificial cow. If I remember it right, they built some sort of artificial digestive system with a fake udder. They couldn’t get the liver’s complicated functions right, so they used a real cow’s liver surrounded by enough of a life support system to keep the liver alive…and growing. Thus, they had both fresh milk to drink and liver trimmings to eat. Cool idea. Except for the liver part. That I could do without.

It would be far easier to get yourself a loop ileostomy. Then you could strap your incinerator to the outside of your body, over the stoma. This would allow you to hook it to wall power several times a day rather than swallowing all those batteries all the time. The incinerator could squirt an adjustable percentage of your chyme back into the downstream loop of the stoma, based on daily body weight measurements. The radiator fins do get a bit hot, though, so no synthetic fabrics from the waist up, please!

As long as we are indulging our Frankensteinian surgical impulses, I would like to advertise my revolutionary techiques for the control of GI bleeding of unknown origin: the total entrectomy with pharyngo-anal pullup/vertebral debulking procedure (the ‘brossa I’), or the much quicker oro-anal anastomosis (the ‘brossa II’). In cases where ligamentous calcification precludes oro-anal anastomosis, it may be necessary to connect a GI fellow into the circuit.