# Digestive system question, possible TMI **URL:** \ **Category:** Factual Questions\ **Created:** [August 8, 2005, 4:54am UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077 "2005-08-08T04:54:20Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Thin\_Lizzy](https://avatars.discourse-cdn.com/v4/letter/t/e9a140/32.png) [@Thin\_Lizzy](https://boards.straightdope.com/u/Thin_Lizzy)\ **Post date:** [August 8, 2005, 4:54am UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/1 "2005-08-08T04:54:20Z")
Ok in school I remember being taught that digesting food takes 24 hours. So how come when I eat certain foods I can see them in the toilet bowl an hour or so after I eat them? ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [August 8, 2005, 6:44am UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/2 "2005-08-08T06:44:59Z")
You can’t. Unless you’re really sick (and then you probably are too sick to care). It takes longer than that for food to go thru your digestive tract. In fact, it usually takes up to 2 hour for foods to jut go thru your stomach. Some foods (fats, carbs) are digested in just 3-4 hours, others like proteins take longer. But these are _digested_, so they aren’t coming out the outer end for you to see. I think you are miscalculating this. ---
**Author:** ![Eleusis](https://avatars.discourse-cdn.com/v4/letter/e/f4b2a3/32.png) [@Eleusis](https://boards.straightdope.com/u/Eleusis)\ **Post date:** [August 8, 2005, 7:44am UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/3 "2005-08-08T07:44:20Z")
> [@](#): > > But these are _digested_, so they aren’t coming out the outer end for you to see. You’ve never eaten corn? ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [August 8, 2005, 9:19pm UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/4 "2005-08-08T21:19:41Z")
> [@Eleusis](#): > > You’ve never eaten corn? Frequently. Heck, we usually grew 20 acres or so of sweet corn on the farm, and ate a lot of it. But again, the kernals you see coming out that end are _undigested_ ones. Most of them, that were digested, you won’t recognize. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [August 8, 2005, 9:55pm UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/5 "2005-08-08T21:55:58Z")
Normal digestion pretty much follows the standard bell curve, with the peak somewhere around ten hours for entry to exit but lots of variation on each end. There’s a billion or so ways for people to not have normal digestion, with the food taking either much faster or much slower than normal. Corn kernels are one of the classic foods to show up in the stool, because people tend not to chew the kernels properly, but just swallow them with a gulp. If they remain whole they are remarkably resistant to the normal breakdown by acids and enzymes. Peas and other foods that are small and have a hard outer coating are like this as well. Food that is going to be digested tends to linger in a thin but vital layer of stagnant water next to the microvilli on the insides of the intestines, which gives the body a better chance of absorbing the nutrients that otherwise would be pushed along by peristalsis in the chyme, the liquid mass that food turns into. Large, undigestible particles are going to stay in the chyme and take less time to go through the body. But an hour? I have my doubts. I’m betting that the “or so” in the OP is really a lot longer than that. ---
**Author:** ![Waenara](https://avatars.discourse-cdn.com/v4/letter/w/50afbb/32.png) [@Waenara](https://boards.straightdope.com/u/Waenara)\ **Post date:** [August 9, 2005, 3:15am UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/6 "2005-08-09T03:15:09Z")
> [@Exapno Mapcase](#): > > But an hour? I have my doubts. I’m betting that the “or so” in the OP is really a lot longer than that. I’m not the OP, but I was pondering posting a similar question recently. Normally I’d say that my digestion takes a normal amount of time (12-24hours). TMI! However, I have noticed that when I eat fast-food hamburgers, it seems speeded up. I can eat fast food chicken burgers or mexican or whatever without problems. But if I eat a burger from, for example, McDonald, then I’m _urgently_ only the toilet in one hour or less. With noticably runnier than normal stools. I don’t think it’s just a case of having an upset stomach and then mis-attributing it to recently eating a burger. It’s happened on at least four or five separate occasions spread over several years. Like I said, it’s only if I have a fast-food burger, and it’s usually worse if I have a burger and fries combo. Maybe it’s all the grease? Dunno. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [August 9, 2005, 4:12am UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/7 "2005-08-09T04:12:31Z")
Google for “gastrocolic reflex.” The simple version can be found [here](http://www.myelitis.org/newsletters/newsletter5-2-06.htm). > [@](#): > > Taking advantage of the body’s natural reflexes and biomechanics should always be used if possible. One example is that of the gastrocolic reflex. This is the body’s natural response to a full stomach. After a meal, the stomach becomes stretched and messages are sent telling this to the brain. Involuntary squeezing of the smooth muscles of the gut occurs in waves, known as peristalsis. The food is digested as it moves through the small bowel and then into the large bowel. It becomes more formed as it moves closer to the rectum. As the waves of peristalsis occur, the bowel contents are moved along. What we perceive is sometimes cramping or gas or “the feeling that it is time to go.” This reflex occurs even if one can not feel it or perceive it. Some people have a very strong reaction after meals and some do not. Those that say, “I am like clockwork; I go to the bathroom every morning after breakfast no matter what” are usually ones with a strong gastrocolic reflex. One way to tell if you have a strong gastrocolic reflex and to identify other toileting patterns is to keep a diary of toileting habits for one to two weeks. Variables to track include bowel movement timing and if there is an association with incontinence or not. Every two hour undergarment checks may be necessary for those that have no awareness of when they go. Bathroom habit trackers should also provide information such as size and consistency of the stools. But [many people](http://www.helpforibs.com/footer/gastrocolic.asp) have begun to associate some of the symptoms of Irritable Bowel Syndrome with the gastrocolic reflex" > [@](#): > > However, how the digestive tract is supposed to work is not exactly how it does work for those who have IBS, and the key problem seems to be with the gastrocolic reflex. Specifically, research has found that many IBS patients have highly abnormal ones. The colons of IBS patients have disorganized and significantly more violent and prolonged contractions (leading to diarrhea), or almost no contractions at all (resulting in constipation). Check the rest of that page as well. I have no idea whether any of this applies to you. However, there are medications that will reduce bowel spasms and excess motility. It wouldn’t be a bad idea to make an appointment with a gastroenterologist. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [August 9, 2005, 4:22am UTC](https://boards.straightdope.com/t/digestive-system-question-possible-tmi/316077/8 "2005-08-09T04:22:39Z")
> [@Waenara](#): > > I’m not the OP, but I was pondering posting a similar question recently. Normally I’d say that my digestion takes a normal amount of time (12-24hours). > > TMI! > > However, I have noticed that when I eat fast-food hamburgers, it seems speeded up. I can eat fast food chicken burgers or mexican or whatever without problems. But if I eat a burger from, for example, McDonald, then I’m _urgently_ only the toilet in one hour or less. With noticably runnier than normal stools. > > I don’t think it’s just a case of having an upset stomach and then mis-attributing it to recently eating a burger. It’s happened on at least four or five separate occasions spread over several years. Like I said, it’s only if I have a fast-food burger, and it’s usually worse if I have a burger and fries combo. Maybe it’s all the grease? Dunno. Many people have laxative effects after various eating fast foods (esp hamburgers) , but it’s not your _digestion_ speeding up, it’s your colon.