If you’ve ever thought your poo is just a bunch of dead cells, think again. Most of it is alive, teeming with billions of microbes. Here’s what studies in healthy adults reveal makes up our poo.
Our feces is largely (75%) made up of water, although this differs from person to person.
Vegetarians have a higher water content in their stools. Those who consume less fiber and more protein have a lower water content. Fiber has a high water-carrying ability and makes our stools more bulky, increases the frequency of bowel movements and makes the process of passing bowel motions easier.
The other 25% of feces is made up of solids, which are mainly organic (relating to living matter) materials. A small proportion of solids is made up of inorganic material such as calcium and iron phosphate as well as dried constituents of digestive juices.
Around 25-54% of the organic material is made up of microbes (dead and living), such as bacteria and viruses.
Our poo is teeming with microbes, most of them alive.
Bacteria in feces have been extensively studied. It’s estimated there are nearly 100 billion bacteria per gram of wet stool.
One study that looked at a collection of fresh stools in oxygen-free conditions (as oxygen can damage certain types of bacteria) found almost 50% of the bacteria were alive.
The different types of bacteria present in feces can influence how hard or loose stool samples can be. For example, Prevotella bacteria, which can be found in the mouth, vagina and gut, are more commonly seen in those with soft stools. In fact, a high-fiber diet is strongly associated with these bacteria.Read more