I have been asked by Colby students this week why eating in Colby's dining halls gives them diarrhea.   Not just one student; several students.  Someone had told one patient that it was Maine State Law to add laxatives, "to keep things flowing smoothly."  Is that smooth flowing in the college's pipes or smooth flowing in the students' bowels? Who is in charge of rumor control around here? And when did, "how is your poop?" get to be a popular dining hall discussion topic anyway? 

Students have been complaining of "diarrhea" and have been associating this with meals/dining, thus the leap to "meals are causing the diarrhea." This is not good science. 

First, some definitions. I was taught in medical school that "if you can't throw it, it's diarrhea." Upon closer questioning, the term "diarrhea" for most students actually means several loose (not hard, formed ) bowel movements a day.  This may have multiple causes and mandatory laxatives or even infections in the dining halls (viruses or bacterial) are not at the top of my list.

The digestive tract is one long tube of smooth muscle and contractions in one area can stimulate contractions in another.  Food moving from the mouth to the stomach by peristalsis (the sequential movement of the muscle) can trigger similar peristalsis lower in the GI (gastro-intestinal) tract.  This can even stimulate a bowel movement.  This gastro / colic reflex ("stomach / colon" reflex) is normal.

How "loose" or watery stool is depends on how much fiber is present in proportion to how much water.  This is mostly a dietary factor.  Fiber is roughage that your body doesn't digest but expels as waste, mostly the pulpy/stringy parts of fruits and vegetables or the husks and hulls of grains. Depending on how much fiber one eats in their diet and how much water is drawn into the intestine, stool can vary from very hard to very chunky, very soft or even watery.  Need I go on with the descriptors? As you are probably aware if you have ever eaten corn on the cob, some food is actually passed in entirety and barely digested at all. Other dietary factors affecting the water balance are artificial sweetners, the new undigestible fat substitutes, medications and herbal/alternative remedies.

Another factor determining the consistency of stool is how much time it spends in the intestine. (Sounds like Fantastic Voyage, huh?) If the roughage passes through quickly there is less time for the intestines to recycle the water and it may be loose.  If one only passes a bowel movement every few days, all the water may be absorbed by the body and the stool becomes hard and difficult to pass (constipation.)  Sometimes three stools a day simply means you had incomplete evacuation the first time. Come to the Health Center to see a picture of how long your large intestines are and you'll understand more clearly how long it can take to clear out. More than one movement a day doesn't necessarily mean "diarrhea." Other factors affecting transit time include stimulants like caffeine and nicotine.

NOW, for a caveat. Transit time, how much absorption of nutrients and water you get from food, how often you actually have access to a bathroom and all be overruled by STRESS.  Any Colby students experiencing stress?  How can stress cause loose stool? Stay tuned next week.  (or for a preview, click www.     and look up I BS.)

But don't go blaming laxatives in the dining halls for your  loose bowels. But  I did  hear they put salt peter in the water!