Bristol Stool Scale

The Bristol Stool Scale or Bristol Stool Chart is a medical aid designed to classify the form of human faeces into seven categories. Sometimes referred to in the UK as the "Meyers Scale," it was developed by Heaton at the University of Bristol

University of Bristol

The University of Bristol is a university in Bristol, England. One of the so-called "red brick" universities, it received its Royal Charter in 1909, although its predecessor institution, University College, Bristol, had been in existence since 1876...

 and was first published in the Scandinavian Journal of Gastroenterology in 1997. The form of the stool depends on the time it spends in the colon

Colon (anatomy)

The colon is the last portion of the digestive system in most vertebrates; it extracts water and salt from solid wastes before they are eliminated from the body....

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The seven types of stool are:

• Type 1: Separate hard lumps, like nuts (hard to pass)
• Type 2: Sausage-shaped, but lumpy
• Type 3: Like a sausage but with cracks on its surface
• Type 4: Like a sausage or snake, smooth and soft
• Type 5: Soft blobs with clear cut edges (passed easily)
• Type 6: Fluffy pieces with ragged edges, a mushy stool
• Type 7: Watery, no solid pieces.

The Bristol Stool Scale or Bristol Stool Chart is a medical aid designed to classify the form of human faeces into seven categories. Sometimes referred to in the UK as the "Meyers Scale," it was developed by Heaton at the University of Bristol

University of Bristol

The University of Bristol is a university in Bristol, England. One of the so-called "red brick" universities, it received its Royal Charter in 1909, although its predecessor institution, University College, Bristol, had been in existence since 1876...

 and was first published in the Scandinavian Journal of Gastroenterology in 1997. The form of the stool depends on the time it spends in the colon

Colon (anatomy)

The colon is the last portion of the digestive system in most vertebrates; it extracts water and salt from solid wastes before they are eliminated from the body....

.

The seven types of stool are:

• Type 1: Separate hard lumps, like nuts (hard to pass)
• Type 2: Sausage-shaped, but lumpy
• Type 3: Like a sausage but with cracks on its surface
• Type 4: Like a sausage or snake, smooth and soft
• Type 5: Soft blobs with clear cut edges (passed easily)
• Type 6: Fluffy pieces with ragged edges, a mushy stool
• Type 7: Watery, no solid pieces. Entirely liquid

Types 1 and 2 indicate constipation

Constipation

Constipation, costiveness, or irregularity is a condition of the digestive system in which a person experiences hard feces that are difficult to expel. This usually happens because the colon absorbs too much water from the food...

, with 3 and 4 being the "ideal stools" especially the latter, as they are the easiest to pass

Defecation

Defecation is the final act of digestion by which organisms eliminate solid, semisolid or liquid waste material from the digestive tract via the anus. Humans usually defecate from three times a week, up to three times a day...

, and 5–7 being further tending towards diarrhoea or urgency.