Stool production: what is normal and what influences it?
So, what is normal?
Normal stool (faeces) output is 150-200g a day - the large intestine receives about 600ml of chyme (partly digested food) from the small intestine in a day and reduces this to 150-200g of stool.
Did you know? Bowel frequency in a healthy person may vary from between three times a day to three times a week.
Using your search engine of choice, type in “Bristol Stool Chart” to find a diagnostic medical tool designed to classify human faeces into seven categories.
How easy do you think it is to use the Bristol Stool Chart? Share your thoughts with fellow learners.
Stool transit time
It takes approximately six hours for the food to be propelled from the mouth to the start of the large bowel, the caecum. When it reaches the caecum it is now ‘faecal matter’. It can then take any time, up to 72 hours in some individuals, for the faecal matter to travel from the caecum to the rectum.
|Small Intestine||3-6 hours|
Total transit time 17-70 hours
What influences stool transit time?
Colonic activity is regulated by the sympathetic, parasympathetic and enteric nervous systems. (We will be looking at the nervous control of the bowel later on this week).
Did you know? The longer the faeces remain in the colon the more water will be absorbed.
A slow bowel transit will result in dry, small, hard constipated type 1 stool (on the Bristol Stool Chart), which is often difficult to evacuate.
Constipation is a large bowel (colon) problem (again, we will be discussing this in more detail later this week).
A fast bowel transit will result in loose/watery stool, types 5/6 on Bristol Stool Chart. These stool types are often difficult to ‘hold on to’ and could result in ‘intestinal hurry’, diarrhoea or faecal incontinence.
Think about how you would answer the following questions, which are commonly asked by people experiencing bowel problems:
What is a normal stool?
Think about colour, smell, consistency, frequency, amount, effort/ease of evacuation, comfort after evacuation.
What affects transit time?
Think about emotions, exercise, sleep, diet/fluids – type/amount/eating pattern, personality.
What affects bowel function?
Think about holidays, shift work, stress, anxiety, illness, change in routine, poor or lack of toilet facilities, failure to respond to call to stool.
Don’t forget to capture your thinking in your learning log or portfolio.
Heaton KW, Radvan J, Cripps H, Mountford RA, Braddon FE, Hughes AO. Defecation frequency and timing, and stool form in the general population: a prospective study. Gut. 1992;33(6):818-824. [Cited 31 July 2018] Available from: https://gut.bmj.com/content/33/6/818
© Association for Continence Advice. CC BY-NC 4.0