The Power of Poo:
What your poo says about you


A taboo topic not often discussed at dinner tables or social gatherings, poo is definitely one of those bodily substances most people shy away from ever talking about. That smelly brown stuff contains a fascinating galaxy of microbes (a fancy word referring to bacteria, viruses, and archae), some dead, but many also still alive. This is in addition to various plant fibres and nutrients which help form its bulk.

What’s so cool about poo?

A marker of your health
It’s hard to describe poo (too gross, too embarrassing, too weird!), so clinicians invented a visual chart called The
Bristol Stool Chart which shows people 7 types of poo, classified based on its consistency. Being able to point as a picture is much easier than having to get descriptive. Together with other information like colour, smell and frequency, this informs clinicians on your diet, hydration levels, possible infection, or even unwanted internal bleeding.

A national disease trackerDuring the COVID-19 pandemic, UK scientists and epidemiologists were able to trace infection rates and areas through sewage systems, as people shed the virus through using the toilet or blowing their nose, which ultimately end up in sewage. The programme helped identify where the virus was circulating in England as well as detecting mutations of the virus. It provided an easily accessible pool of information right under our feet. While public health campaigns may not have been able to convince people to take regular swab tests, you can’t stop people from doing the natural process of using the toilet.

A modern medication?A relatively new treatment method called a faecal transplant involves taking someones poo, all it’s bacteria included, and moving that into someone else's. The transplanted ‘good’ poo re-colonizes ones gut with a different community of ‘good’ bacteria. They surpass the impact of diet, probiotics and prebiotics, as they essentially deliver an entire ecosystem of microbes at once. It is already one of the mainstay treatments for recurrent infections with a nasty bacteria called C.diff, and more research is being done into it’s use for mental health conditions such as depression as well. Whilst research in this area is still early days, and mainly in animals, it isn’t ridiculous to envision a future where pharmacy shelves are stocked with poo pills.

The secret to good health in later life?
Researchers at Harvard Medical School are looking into the use of autologous faecal transplants as preventative medicine. This essentially means storing up a poo sample when you’re young and healthy (and have a diverse range of gut bacteria), and transplanting this to yourself at a later stage in life - like egg freezing. The theory behind this is that individuals with greater gut biodiversity are more likely to live longer, healthier lives. The US has already gotten the ball rolling with the world's first public stool bank at OpenBiome.


There is clearly far more than meets the eye when it comes to poo. Your poo could be diagnostic, therapeutic, and if anything else, a fun topic to bring to your next dinner party. Perhaps you’ll think twice before flushing this wealth of information and data straight down the toilet.

*If you are concerned about any changes to your stool, it is advisable to seek consultation from a medical professional

Written by Dr. Julia Craggs, March 2024