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Date of last update: 10/15/2017.

Forum Name: Gastroenterology Topics

Question: Diarrhea several hours after eating cereal

 DJMicDaddy - Mon Dec 07, 2009 3:00 pm

I've been experiencing this problem for a couple years now. I'm not lactose-intolerant, I know that for sure. I'll eat cereal in the morning (any kind of cereal) at around 6:00-7:00 a.m.. A three to four hours after I eat the cereal, I begin to experience frequent gas, and it's pretty bad smell-wise. By the time the afternoon comes around, usually around 1:00-2:00, I can feel and hear my intestines churning frequently, and I know it's almost.... time. Around 2:00-3:00, it's bathroom, and I of course have diarrhea. It might take two sitting to get it all out.

I do not experience stomach aches or anything like that, except maybe the occasional discomfort from intestinal pressure caused by gas. I've taken Pepto-Bismol chewables and liquid to see if it would help a couple times, and it did, as far as I could remember. I didn't do this frequently at all, though.

It's not a big deal to me, but it's frustrating at times, and of course uncomfortable. If anyone has any idea what this might be a result of, I'd appreciate the information!


 Dr.M.Aroon kamath - Sun Dec 20, 2009 10:00 am

User avatar Hi,
It appears that you(your intestines) are having difficulty handling certain foods(perhaps cereals).

Intake of high-fiber cereals - especially those that contain high 'soluble' fiber(Found in oat bran, barley, nuts, beans, peas, seeds, lentils,and most fruits). Soluble fiber is not broken down until it reaches the large gut where digestion causes gases to form.

'Insoluble' fiber on the other hand, increases fecal bulk (found in wheat bran, whole grains) and does not produce gases.

The next condition one has to keep in mind is 'celiac disease'- a disorder wherein the digestive system is damaged by the immune response to a protein called gluten, which is found in wheat, rye, and barley and a wide range of foods,including breakfast cereals. People with celiac disease have difficulty digesting & absorbing the nutrients food and may experience abdominal pain, bloating, diarrhea, exhaustion, and depression when they eat foods containing gluten. Symptoms can be managed by adhearing a gluten-free diet.

Apart from the cereals themselves, especially if you are eating commercially available 'breakfast cereals' , one needs to think of some of the additives and preservatives causing this kind of a problem.

In passing, one of the causes (which is difficult to prove), needs mention....
Fungal toxin deoxynivalenol (DON) is one of the most commonly found mycotoxins in cereal and grain crops (barley, maize wheat, and their by-products) from North America and Europe(contaminated by certain toxic moulds). Acute toxicity due to DON is said to be associated with diarrhea, vomiting, internal bleeding and even mortalitiy.

To identify which particular cereal may be the culprit, it may be necessary to try by trial and elimination.
Best wishes!

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