Question: wat does poo tell us about anything

Ciarán O'Brien answered on 10 Nov 2014:

Oh, you can tell a lot about a person from their poo!

Many diseases attack your stomach or gut, so if you find certain bacteria or viruses or worms or other parasites in someone’s poo you’ll know they have that disease and you’ll know how to cure it. Other diseases cause certain chemicals to wind up in your poo, and we can check for them and find out why a person is sick, and work out from there how to make them better.

When you were born, you had no bacteria living in your gut at all, you got most of them from your mother when you popped out! We can tell how a person was born from their poo as well, because depending on how you were born, you would have picked up different bacteria from your surroundings.

You can tell a lot about their diet from poo as well. If you eat too many fatty foods or too much meat/protein, you’ll encourage certain bacteria to grow in your gut and others will die out, and we can tell if your poo contains very large numbers of a certain bacteria, that you’ve been eating too much of some food type and need to balance it out with other foods.

The amount of protein/fatty acids in poo can also tell you how regularly and how well someone eats, which lets you make a very good guess at how well off they are. Rich people can afford to eat meat regularly, while a broke student starving in college might only be able to afford a pack of Aldi noodles every other day. One of the other people in my lab is currently looking at certain types of fatty acid in poo and seeing if they can be used to determine whether a person is at risk of suffering depression. We think they can, but we’ll find out soon enough when the experiments are run.

Later on I’ll be doing experiments on poo from children who went to Crumlin Hospital, to see if we can use their poo to figure out how they develop allergies and asthma and other things like that. The bacteria that start to live in your gut and come out in your poo are the very first foreign cells your body’s immune system meets, so the type of bacteria living in your gut help train your immune system to recognise threats and leave good bacteria alone. We think that children who didn’t start off with the right bacteria end up with an immune system that isn’t fully trained, and that can cause allergies.

So yeah, poo tells us a lot of things. Listen to your poo!