The fascinating world of faeces holds many secrets, including the reason behind its distinctive brown colour. Dr Rina Fu, help us delve into the science behind poop!

Why is poop brown?

Our digestive journey begins in the mouth and ends in the large intestine. Along this path, undigested fibres and food particles undergo a complex process of absorption and transformation. Ultimately, the colour of faeces is influenced by bile, a chemical produced by the liver. Bile acts as a soapy detergent, aiding in the breakdown of fats, cholesterol, and fat-soluble vitamins essential for cell membranes. Moreover, bilirubin, a by-product of red blood cell breakdown, contributes to the brown hue of faeces.

Coprology: The Science of Poop

In the realm of science, poop is formally known as faeces, and the study of faeces is called coprology. In diagnostic pathology labs, experts analyse stool samples to uncover clues about digestive health, detecting parasites, bleeding, and other abnormalities. “We get patient samples, they might have a tummy ache or something…We’ll test it out, particularly for parasites, cyst, or if there’s bleeding or that kind of thing. We would look at it under the microscope and look at the consistency in the colour as well.”

The Bristol chart helps coprologists categorise stool consistency, ranging from pebble-like to fluffy textures. An ideal stool resembles a soft banana, indicating healthy digestion. Deviations from this norm, such as diarrhoea or constipation, warrant attention and possibly medical intervention.

The Aroma of Poop: What It Reveals

The distinctive smell of faeces is influenced by diet, gut bacteria, and metabolic processes. Consumption of fatty foods and meats can intensify odour, reflecting the composition of intestinal bacteria. For children using a potty, the absence of water can amplify the smell, offering valuable clues about gut health. “Generally, if you eat fatty stuff, processed food, and lots of meat, you’re gonna get a really strong smell.

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