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  #1  
Old 05-23-2008, 01:35 PM
I Have Hippos In My Garden I Have Hippos In My Garden is offline
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How long does food stay in your stomach?

Once you have swallowed and your food has reached your stomach, how long does it take for it to completely be digested and for your stomach to become completely empty again?

Does it depend on the food?

Are there some foods that are digested immediately and others that will linger in your stomach for longer, or is a meal containing lots of different food just digested all in one go at the same speed?
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  #2  
Old 05-23-2008, 01:55 PM
Shagnasty Shagnasty is offline
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I got sick recently and I can confirm that there are still some recognizable bits of a Taco Bell meal six hours after I ate it.
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  #3  
Old 05-23-2008, 02:05 PM
Rhythmdvl Rhythmdvl is offline
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Quote:
Originally Posted by Shagnasty
I got sick recently and I can confirm that there are still some recognizable bits of a Taco Bell meal six hours after I ate it.
Um, the OP said “food.” I’m not sure your example counts


According to this page from Colorado State University, the times vary on a lot of factors. They did provide some interesting times:
  • 50% of stomach contents emptied 2.5 to 3 hours
  • Total emptying of the stomach 4 to 5 hours
  • 50% emptying of the small intestine 2.5 to 3 hours
  • Transit through the colon 30 to 40 hours
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  #4  
Old 05-23-2008, 03:00 PM
I Have Hippos In My Garden I Have Hippos In My Garden is offline
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Um, the OP said “food.” I’m not sure your example counts
I'm not even sure i know what a Taco Bell is :s
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  #5  
Old 05-23-2008, 03:01 PM
I Have Hippos In My Garden I Have Hippos In My Garden is offline
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Quote:
According to this page from Colorado State University, the times vary on a lot of factors. They did provide some interesting times
Interesting thank you. Nothing seems to happen immediately then?
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  #6  
Old 05-23-2008, 03:08 PM
FourPaws FourPaws is offline
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Quote:
Originally Posted by Rhythmdvl
Um, the OP said “food.” I’m not sure your example counts


According to this page from Colorado State University, the times vary on a lot of factors. They did provide some interesting times:
  • 50% of stomach contents emptied 2.5 to 3 hours
  • Total emptying of the stomach 4 to 5 hours
  • 50% emptying of the small intestine 2.5 to 3 hours
  • Transit through the colon 30 to 40 hours
How then, based on these numbers, can I erm, "recognize" things I had for lunch (that I hadn't eaten previously unless weeks prior) in the span of a few hours?
/not a whoosh, just curious
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  #7  
Old 05-23-2008, 03:43 PM
Rhythmdvl Rhythmdvl is offline
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Again, the list was averages—the main thrust of the linked page was describing why the question is hard to answer. Also, consider that if it’s an average of 2.5–3 hours for half the contents to leave the stomach, that means that four to five hours there’s still a bunch of stuff left in there. I don’t suspect the curve is linear, but half a chicken ‘n rice dish is still a lot to recognize after a purge. Lastly, I bet the above times are for a well-functioning digestive situation. Eat something that gives cause to give it back, and it may be likely that there are other things at work keeping the normal process from taking place.

There’s also the other end of the spectrum. I don’t want to devolve into TMI-achusetts, but I’ve seen things that made speedy trips through the digestive system without necessarily having unusual catalysts.

I think it not only prudent, but apropos to mention that I’m mainly talking out my ass—most of this was just found via Google. IANAD

Last edited by Rhythmdvl; 05-23-2008 at 03:44 PM.. Reason: colon clensing
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  #8  
Old 05-23-2008, 03:59 PM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by I Have Hippos In My Garden
Are there some foods that are digested immediately and others that will linger in your stomach for longer, or is a meal containing lots of different food just digested all in one go at the same speed?
The stomach doesn't do much real digesting of food at all. Digestion in this sense means the breaking down of proteins into amino acids, carbohydrates into simple sugars, and fats into fatty acids. Those are the components of food that can be moved through the barriers in the intestines into the blood stream.

The stomach serves mostly to break coarse food into a semi-liquid stream (called chyme, pronounced with a "k" sound) that will move easily through the intestines so that the enzymes can work on the particles to digest them. The hydrochloric acid in the stomach serves to break down the structure of food and also to activate the pepsin enzyme, which helps digest proteins.

Peristaltic waves move through the stomach at about a rate of three per minute. These squeeze out any liquids that can slip easily through the pyloric valve into the duodenum, the first section of the small intestine. Water, and other beverages that are mostly water, can start moving out of the stomach almost immediately, although the amount that will go through the valve at any one moment is small enough that even a glass of liquid will probably take an hour to leave the stomach entirely.

It can take several hours for all the food to empty, by which time you've probably added more food. Your stomach is therefore working all day long.

If you swallow someone that's not digestible it will sit there until the stomach can squeeze it out, assuming that's possible.

Quote:
Originally Posted by Four Paws
How then, based on these numbers, can I erm, "recognize" things I had for lunch (that I hadn't eaten previously unless weeks prior) in the span of a few hours?
But I still don't get this. How are you recognizing these "things"? Where are they coming out and in what form? If you mean seeing whole kernals of corn in the stool, then it's simply a matter of their being small enough to be carried through and nothing much interacts with them because they're indigestible. They're the neutrinos of the digestive tract.
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  #9  
Old 05-23-2008, 05:55 PM
SpoCkss SpoCkss is offline
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What about glucose, sacarose and starch guys? How long does it take from the moment it enters the stomach to the moment it goes to the blood?
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  #10  
Old 05-23-2008, 07:29 PM
FourPaws FourPaws is offline
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Quote:
Originally Posted by Exapno Mapcase
But I still don't get this. How are you recognizing these "things"? Where are they coming out and in what form? If you mean seeing whole kernals of corn in the stool, then it's simply a matter of their being small enough to be carried through and nothing much interacts with them because they're indigestible. They're the neutrinos of the digestive tract.
Corn, yes. Peas, yes. Lettuce, yes. Hot peppers (ow), yes. How can they make the trip in one hour (and I am not joking about the timeframe.)
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  #11  
Old 05-23-2008, 09:45 PM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by SpoCkss
What about glucose, sacarose and starch guys? How long does it take from the moment it enters the stomach to the moment it goes to the blood?
Sugars are digested in the small intestine.

Other than that, it depends totally on what food the sugar is hidden in. Sugar in a liquid, like soda pop, will travel to the small intestine fairly quickly. Sugar in solid foods like cake will take longer to get there and have a longer transit time through the intestines. The bigger the meal, usually the longer the transit.

Transit time also varies significantly from individual to individual. That's why the figures Rhythmdvl quoted were averages with large variables. FourPaws, your system is your system. I can't predict anything about any individual.
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  #12  
Old 05-23-2008, 09:58 PM
Ruby Ruby is online now
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Ha. We were just having this discussion this week.

My B-I-L swears that whenever he eats beef, he has to leave the table by the end of the meal to ... um ... poop.

I call bullshit. Nothing, in my uneducated opinion, can enter your mouth and exit your bottom in less than an hour.
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  #13  
Old 05-23-2008, 10:24 PM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by Ruby
Ha. We were just having this discussion this week.

My B-I-L swears that whenever he eats beef, he has to leave the table by the end of the meal to ... um ... poop.

I call bullshit. Nothing, in my uneducated opinion, can enter your mouth and exit your bottom in less than an hour.
It's called the gastrocolic reflex. It's normally a regulator signal sent out from up the digestive tract to the colon, keeping the colon active and food moving.

In some people, especially those with IBS, the signal is much more violent at times and the spasming can cause diarrhea within a few minutes of food being eaten. What leaves the colon is food from earlier meals many hours before, with no relation to anything that's just been taken in. However, that's not the way it feels, says someone who has it.

Check the graph at the link I gave if you want to see something that will make your hair stand on end. (Not necessarily recommending any therapies on that page, but the graph and explanation are good.)

There are a very few people with a condition called rapid transit, in which the time for food to exit is cut unbelievably short, but IBS is more likely since rapid transit affects every single thing you eat.
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  #14  
Old 05-23-2008, 10:59 PM
shijinn shijinn is offline
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Quote:
Originally Posted by Exapno Mapcase
... If you swallow someone that's not digestible it will sit there until the stomach can squeeze it out, assuming ...
you alright Exapno? are you still having nightmares about Jonah?
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  #15  
Old 05-23-2008, 11:12 PM
Exapno Mapcase Exapno Mapcase is offline
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Nightmares? I had a whale of a good time.
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  #16  
Old 05-24-2008, 04:51 AM
SpoCkss SpoCkss is offline
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Quote:
Originally Posted by Exapno Mapcase
Sugars are digested in the small intestine.

Other than that, it depends totally on what food the sugar is hidden in. Sugar in a liquid, like soda pop, will travel to the small intestine fairly quickly. Sugar in solid foods like cake will take longer to get there and have a longer transit time through the intestines. The bigger the meal, usually the longer the transit.

Transit time also varies significantly from individual to individual. That's why the figures Rhythmdvl quoted were averages with large variables. FourPaws, your system is your system. I can't predict anything about any individual.
Lets say it's not hidden at all. That you ate pure glucose. How long would it take?

I think it has to do with glycemic index, the higher GI the faster it goes to the blood. Glucose is on the top, so it should go fast, on the other hand, white bread is also close to the top, which i don't get since it's a solid, and it has to go from starch to maltose to glucose.
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  #17  
Old 05-24-2008, 10:45 AM
Muffin Muffin is online now
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Quote:
Originally Posted by Ruby
. . . he eats beef . . . I call bullshit . . .
What do you call if he eats chicken?
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  #18  
Old 05-24-2008, 11:02 AM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by SpoCkss
Lets say it's not hidden at all. That you ate pure glucose. How long would it take?

I think it has to do with glycemic index, the higher GI the faster it goes to the blood. Glucose is on the top, so it should go fast, on the other hand, white bread is also close to the top, which i don't get since it's a solid, and it has to go from starch to maltose to glucose.
As this Wiki page shows, white bread has a much lower GI than glucose, 140 to 100 when white bread is used as the reference. That page also has a graph for blood sugar increase times.

Note that the reference index is also an average of different peoples' response times, so we're still talking about approximations that doesn't necessarily apply to you as an individual.

Why does white bread break down so fast? It's the nature of the carbohydrate.

http://www.fao.org/docrep/W8079E/w8079e0k.htm
Quote:
Digestion and absorption of carbohydrates

Polysaccharides and oligosaccharides must be hydrolyzed to their component monosaccharides before being absorbed. The digestion of starch begins with salivary amylase, but this activity is much less important than that of pancreatic amylase in the small intestine. Amylase hydrolyzes starch, with the primary end products being maltose, maltotriose, and a -dextrins, although some glucose is also produced. The products of a -amylase digestion are hydrolyzed into their component monosaccharides by enzymes expressed on the brash border of the small intestinal cells, the most important of which are maltase, sucrase, isomaltase and lactase (69). With typical refined Western diets, carbohydrate digestion is rapid and carbohydrate absorption occurs primarily in the upper small intestine. This is reflected by the presence of finger-like villi in the mucosa of the upper small intestine, with wider and shorter villi in the lower half of the small intestine. However, carbohydrate digestion and absorption can occur along the entire length of the small intestine, and is shifted toward the ileum when the diet contains less readily digested carbohydrates, or when intestinal glucosidase inhibitors which may be used to treat diabetes are present. In this situation, the upper small intestine exhibits wide villous structures with leaf-like arrays, while in the ileum the villi become longer and more finger-like.
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  #19  
Old 05-24-2008, 08:13 PM
Blalron Blalron is offline
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Originally Posted by I Have Hippos In My Garden
I'm not even sure i know what a Taco Bell is :s
It's a fast food restaurant that serves tacos and other "mexican food." I guess you folks over in the UK don't have any. Don't worry, you haven't missed anything.
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  #20  
Old 05-25-2008, 02:03 PM
I Have Hippos In My Garden I Have Hippos In My Garden is offline
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t's a fast food restaurant that serves tacos and other "mexican food." I guess you folks over in the UK don't have any. Don't worry, you haven't missed anything
Ah I see. No we don't have them, or anything close come to think of it.
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  #21  
Old 05-25-2008, 02:16 PM
BobT BobT is offline
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I have had the feeling of eating beef and having to make a quick trip to the bathroom. It's only certain cuts, which I imagine has something to do with the amount of fat in the food.

In Southern California, there is a famous restaurant called Lawry's (it's in other cities too) that serves cuts of prime rib that are usually big enough to feed a family of eight for a week. I had a small piece, but I still ended up in the bathroom before I left the restaurant. And there were two other men in the restroom with similar maladies.

This is not to say that the prime rib wasn't good.
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  #22  
Old 05-25-2008, 03:34 PM
Bosstone Bosstone is offline
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Quote:
Originally Posted by Ruby
My B-I-L swears that whenever he eats beef, he has to leave the table by the end of the meal to ... um ... poop.

I call bullshit. Nothing, in my uneducated opinion, can enter your mouth and exit your bottom in less than an hour.
Heh. I have the same argument with my roommate. Chinese food, especially stirfry, usually forces me to the bathroom less than half an hour after eating it. And if it was particularly spicy...yeah, I feel it right away. I've had to stop eating at certain restaurants because it got so bad. But my roommate insists the same thing you do, that food can't just fly through one's system that quickly. Even so, I know what I eat and I know what happens when I eat it.
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