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DigestOk

Gut Transit Time Test

Measuring how long food takes to travel from mouth to toilet is a crucial clinical metric. Normal transit time is generally between 12 and 48 hours. Based on the validated "Blue Poop" methodology (Zoe/King's College London, 2021).

How to perform the test

  1. Prepare a marker food. You need something that passes through undigested and is highly visible. Clinical standards use bright blue food dye (e.g., in a muffin) or a large serving (2 tablespoons) of white sesame seeds swallowed whole.
  2. Eat the marker. Note the exact time and date you consume it. Do not eat it over several hours; consume it in one sitting.
  3. Wait and observe. Proceed with your normal diet and routine. Check your stool every time you have a bowel movement.
  4. Log the exit. Note the time when you first see the marker (blue color or seeds) in your stool.

What your results mean

  • Under 12 hours: Rapid transit. Often correlates with diarrhea, malabsorption, or hyperthyroidism.
  • 14 to 48 hours: Normal transit. Indicates a healthy, diverse microbiome.
  • Over 48 hours: Delayed transit. Clinically classified as slow-transit constipation, affecting microbial diversity.

Transit Time Calculator