Intestinal Transit Time: The Red Poop Challenge

What can your poop tell you about the tiny bacteria that live inside your intestines? Quite a bit! 

Researchers in London recently found a way to figure out intestinal transit time, or how long it takes for you to ingest something, absorb the nutrients and then for it to leave your body as poop.

We all have bacteria in our intestines which help us digest food and process nutrients. Current research being done all over the world is trying to determine the optimal types and amounts of bacteria to have. The easiest way to do this is by studying poop (stool).

While studying the bacteria in your stool can be done in a lab, the researchers wanted to find an easy way to do it at home. Their study is based on the fact that the normal, brown color of poop is due to stercobilin. Stercobilin is a chemical which is created inside your body when the healthy bacteria in your intestines interact with bilirubin, a chemical which helps you digest food produced by your liver. Since most stool is characteristically brown, variations in color are usually quite visible!

While there are many sophisticated tests available at the hospital to measure intestinal transit time, they can be invasive, expensive, and time-consuming. However, as the researchers from London realized, there is a simple test you can do at home related to identifying unique colors in your stool: 

1. Consume a food that can be easily identified in the stool by color, like red beets (at least a half to a whole beet) or corn. These foods should be avoided for a day or two before your experiment.
2. Write down when you eat the test foods.
3. Write down when you first see the food (or distinctive color of the food) in your stool.
4. The difference in time from when you first ate the food to when it appears in your stool is your intestinal transit time.

In the study, the average time was about 28 hours, with a range of 12-60 hours being considered normal. It is important to remember many things outside of your intestines can influence the transit time including diet choices, water and caffeine intake, exercise, medications, and overall health, to name a few. However, this quick and easy-to-do home experiment can give some insight into how our intestines (and the bacteria inside of them) work to keep us healthy.