Gut Check Made Simple: The Bowel Transit Test
Your digestive system is a finely tuned machine. One of the easiest ways to get insight into how well it’s working is by measuring your bowel transit time—the length of time it takes for food to move from your mouth to the other end. A healthy transit time is typically between 12 and 48 hours, though this can vary depending on diet, stress, hydration, and individual gut health.
Why Transit Time Matters
Your bowel transit time is a simple, non-invasive marker of digestive health.
Too fast (under 12 hours) may mean your body isn’t absorbing nutrients effectively, leading to deficiencies.
Too slow (over 72 hours) can allow toxins and metabolites to build up, increasing bloating, discomfort, or even risk of inflammation.
Just right suggests your gut is processing food efficiently and supporting healthy elimination.
This test can be particularly useful if you’re experiencing issues such as constipation, diarrhoea, bloating, or irregular bowel habits. It gives both you and your practitioner valuable information for tailoring your gut health plan.
Why Use Corn?
Corn is ideal for this test because the outer shell of each kernel is made from cellulose, a fibre your digestive enzymes can’t break down. While the inside of the kernel is digested, the yellow skins often reappear in stool—making it a natural and visible marker of transit time.
How to Do the Corn Test
Choose your marker meal – Eat a serving of whole corn (about half a cup of cooked kernels). Popcorn or corn on the cob can also work, but plain boiled or steamed kernels are easiest to track.
Note the time – Record exactly when you eat the corn.
Watch and wait – Over the next 12–72 hours, check your bowel movements for the first appearance of corn skins.
Keep observing – Continue to check until the corn has completely disappeared from your stool. This helps determine not just how quickly food enters your system, but also how long it lingers.
Record your results – Write down both the time of first appearance and the time of last appearance.
What Next?
If your transit time is consistently under 12 hours or over 72 hours, it may be worth investigating further with your health practitioner.
To support healthy transit, focus on hydration, fibre-rich foods, daily movement, and stress management.
This simple test is free, safe, and surprisingly insightful. Sometimes the smallest changes—like noting when your body starts and stops seeing corn—can give powerful clues about your gut health.