Gastrointestinal (GI) transit time is the interval between consumption of food and it’s elimination as feces. It’s a handy indicator of digestive health, and by extension, overall health status. It is easy and inexpensive to measure, and often proves helpful in working with patients who have digestive problems.
A transit time between 12-18 hours is considered healthy. But for all too many Americans, the transit time proves to be 36-96 hours or even longer. This is problematic because the longer the fecal material sits and putrefies in the intestines; the more likely it is that toxins will be absorbed.
Long transit times are associated with toxin reabsorption, poor metabolism, and a predisposition toward or amplification of many chronic intestinal or systemic illnesses. It is also associated with intestinal candida (yeast) overgrowth, H Pylori, and SIBO. Improving GI transit time can usually eliminate these issues without medications.
Low intake of dietary fiber is a major factor underlying prolonged transit times in many people. Absence of fiber in the diet requires the body to work harder to ‘push’ wastes along. Clear evidence of a grossly prolonged transit time can sometimes be a strong motivator for patients to make healthful changes in their diets.
Very short transit times (under 10 hours) indicate a different type of problem. In these cases, the GI system does not have adequate time to digest and assimilate what is eaten. In these cases, the patient may be experiencing a form of malnutrition, owing to malabsorption, despite consuming large amounts of food.
GI transit time can be evaluated with a simple home test.