It varies. Foods can cause a reaction for quite sometime, so sometimes even up to a couple of days. Alot depends on what part of the GI tract is where the problems occurs.Food stays in the stomach for about an hourish, so if the stomach reacts to it, it is right aways. From 1-3 hours or so it is in the small intestine, so if the small intestine is the part of the GI tract that is reacting that would be the time frame. The rest of the time it is in the colon, and some reactions could occure there. Gas production generally occurs in the colon, so something that makes you gassy may do so many hours after you ate it.K.------------------I have no financial, academic, or any other stake in any commercial product mentioned by me.My story and what worked for me in greatly easing my IBS: http://www.ibsgroup.org/ubb/Forum17/HTML/000015.html
For me it was in the vincinity of 12-18 hours. Logging a journal is of course very frustrating if you don't know the timing, because most folks consume quite a variety of ingredients during a typical day.Once I understood the timing, it became much clearer. If I ate a food at 7:00 am which would trigger IBS symptoms, then right around 7:00 or 8:00 pm I would start to get some small pain twinges. Full blown symptoms could hit several hours later, while sleeping, or possibly during the morning commute to work. (Oh joy!)If you do have food intolerances, in my opinion the food may have to come into contact with the colon for problems to develop, hence the long lag time. Your mileage may vary.
STACIA:If you want to learn the specifics about this problem, get this book and you will know more than just about anybody concerning food, additives and how and why they can affect your body: http://www.amazon.com/exec/obidos/ASIN/089...r=2-1/102-64875 08-3420903[/URL] it will be the best $18 you ever spend.In the meantime, I will skip [due to time constraints] all the technicalities and physiology of food allergy, immunologic food reactivity, and non-immunologic food reactivity. I simple terms food allergies, regulated by specific immunoglobulins for specific substances, have a rapid and usually dramatic onset after ingestion, followed by a second, delayed reaction half a day later.If you have a real food allergy you often know it by adulthood because the pattern would occur so many times since childhood when you became sensitized that if you did not outgrow it the obviousness of it would defy obliviousness to it. Yet for some this does occur and blind oral challenge or one of the in vitro allergy tests may be helpful. These tend to produce false-positives, so you want to confirm ant test-psoitive food with RAST or ELISA by oral challenge. The mere presence of specific IgE/IgG does not man you are clincilly allergic. Food allergy is a comorbidity with IBS more than people think, though keep in mind it is a comorbidity, not the cause.IF one test-positive, for example, by RAST for soem foods, removes them, and your symptoms all go way completely. Congratulations. You do not have IBS! If they get somehat better but do not go away, congrstulations! You removed a comorbidity from your symptom set and causal set! Please continue.However, based solely on what you wrote, you do not sound like you have food allergy.There are many reasons that immunologic and non-immunologic reactions to foods can be delayed, up to 72 hours from the time the offending substance is ingested and the symptoms are noticed (if at all...sometimes they are subclinical from a single food and only become obvious when 2 or more are ingested together, or a large dose is ingested).These reactions focus around the small intestine (duodenum to ileum) not the colon. By the time you get to the colon the party is over. If you are reactive to it regardless of the mechanism it would have occurred by then. The mechanisms are in the small bowel and the exposure is more than ample.All the possible mucosal immune responses have already had ample opportunity to occur, as well as any cellular immune or non-immune and detoxifiying-enzyme deficiencies will have had ample time to show themselves.This is because the stuff you swallow, chew up, mix with some enzymes in the stomach then shoot into the duodenum has about 6+/- meters of distance to travel to get to the colon. The speed of peristalsis under normal conditions is roughly 1 cm per minute. So if one has a fairly normal transit rate, 600-625 cm will be traversed in about 10 hours or so (from entry to duodenum to exit at the ileocecal junction). Now this is not to say that in some people NOTHING occurs of harm in IBS in the colon. About 40-50% of IBS patients at variosu times have been seen to haveincreased mast cell density at the ileocecal junction, indicating recruitment. Recruitment occurs at a site of chronic insult...a site where they are needed. This indicates that in some patients, there is still some residual reactivity occuring at the ileocecal area (where the small bowel dumps the chyme into the large bowel for water removal an further processing). This just implicate the small bowel contents more clearly.During this time within the small bowel, the chyme formed is being acted upon in vastly interesting ways beyond the scope of this discussion or time, and each and every thing you ingest is being broken down into its components for assimilation, and unneeded things are prepared for removal. Everything is exposed to immune strucutures, first in the inner lining of the small intestine (in the mucosal lining), in the lymphatics in the lining and in the lacteals, and by the other immune cells circulating within the tiny little microvasuculature of the villi in the lining if the intestine. It is a misconception that food partciales are not absorbed through the bowel wall into the microvasculature.thst they must be broken down fully. The normal oral-toelrance mechanisms of the cellular immune system do not respond to partciales that small...they need to 'see" bigger particles to identify and react or not react to. Then of course they are circulating around in the blood with all the various types of immune cells and structures, and each is looked at, identified as friend or foe, and then disposed of by phagocytic (eating cells in the blood).Some stuff is abosrbed directly into the bloodstream through the mucosa in its original form, some is not absorbed until later after digestion. And since immune, non-immune, and inflammatory reactions are all possible singly or together depending upon the bodies 'read' of the substance (or a direct chemical affect) the reaction can take time to develop based upon the transit time as well as the added time for the reaction to occur, the chemicals which cuase symptoms to be perceived to be realesed or synthesized, and to reach a high enough concentration at each effector site to produce perception. Simply stated, sometimes a food contains a toxin which acts directly upon mucosal or cellular structures to damage them and release chemicals which cause a reaction (pseudoallergy). Sometimes the cellular immune system malfunctions and mis-identifies a food particle as FOE and sets of a reaction to kill it as if it were an invader. And sometimes the cells do nothing but a reactions occurs diereclty which damages their integrity and the chemicals are released anyway. In any event the ned result is the same.So to accurately find food intolerances one has to go beyond the usual food-allergy log that we are taught to keep (write down everything you eat and see if it triggers anything). These instructions come from a lack of understanding of the mechanisms, or a failure to acknowledge them, only an understanding of allergy.You have to keep a parallel timeline of ingestion, symptom onset, and time on the same sheet of paper (like take yellow note paper and ake each line a 30 minute point on a 24 hour scale). then have a food/fluid column (include how MUCH you ate too) and another column for symptom and DEGREE of perception.Then track everything by the clock for MORE than a week. This is the second grave error in food sensitivity detection....too short a log time (inadequate data pints, inadequate time). 2 weeks to a month, and then you have to look for PATTERNS. During this time do NOT change your eating habits for the sake of the log based on some dumb advice to do so. That comes AFTER you know WHAT to change.Anyway you have to then study the parallel ingestion-symptom lists looking for PATTERNS. That may be self-evident. When the ingestion-symptom onset cycle is out of synch by up to 72 hours, guess what, one week is not going to tell you jack-you-know-what EXCEPT only the grossest reactivities (small dose, rapid onset of bad symptoms). It will miss many.Even the most carefully crafted log can still miss the moe subtle ones. However, if you do it this way and remove the foods that appear to create a pattern of response, the success rate of elimination has been reported as high as 70% of users achieveing noticeable relief.This is the only reason we develop in vitro tests for food reactivity: it is shortcut, they can detect low levels of response-subclinical-which can mean dose or combiannt reactions, AND it can check additives, something VERY hard to do with a log system. But not impossible at all. Just chemicals are soften impossible to sort out this way.Anyway, hope that helps sort that out. To me, if your dietician does not have form built like that, or you are on your own, get a legal pad. It has all the nice lines yo need to set up the times and columns and keep everything toegther across the sheet.Everything must be logged in the time slot sequentially (ingestant and symptom) when it was ingested or perceived.Hope that helps. Any more question I will try to stop by again on Monday. Gotta run.Eat well. Think well. be well.MNL______________ www.leapallergy.com [This message has been edited by Mike NoLomotil (edited 05-05-2001).]
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