There are seven types of stools (faeces) according to the Bristol Stool Chart. The Bristol Stool Chart or Bristol Stool Scale is a medical aid designed to classify faeces into seven groups.
The type of stool or faeces depends on the time it spends in the colon. After you pass faeces, what you see in the toilet bowl is basically the result of your diet, fluids, medications and lifestyle. You can use the Bristol Stool Chart to check what your stools are telling you.
The Bristol Stool Chart shows seven categories of stool. Every person will have different bowel habits, but the important thing is that your stools are soft and easy to pass – like types 3 and 4 below.
The Bristol Stool Chart was developed by K. W. Heaton and S. J. Lewis at the University of Bristol and first published in the Scandinavian Journal of Gastroenterology in 1997.
Reference: Heaton, K W & Lewis, S J 1997, 'Stool form scale as a useful guide to intestinal transit time'. Scandinavian Journal of Gastroenterology, vol.32, no.9, pp.920 - 924. Retrieved on 2/3/2007.