This page describes how to determine your transit time. Transit time is the interval between consumption and elimination; between food ingestion and excretion of digested waste.


To determine transit time, we recommend the use of charcoal capsules.
These are also sometimes used for the symptomatic treatment of intestinal gas.

Suggested Dosage

Take 6 – 12 capsules (1.5 – 3 grams of charcoal) with 8 ounces of water between meals. Choose a high quality brand of activated charcoal capsules like REQUA. For most accurate result, ingest the capsules just after a bowel movement.

Dosage according to weight:

< 150 lbs: 6 capsules

150 – 200 lbs: 8 capsules

200- 250 lbs: 10 capsules

> 250 lbs: 12 capsules

Note (record) the time: This marks the beginning of the transit time test.

You may examine the consistency of your excreted stool. Note anything unusual or changed about the quality, such as texture, color, and composition. For example, does it float or sink? Does it have a strong odor? Is it solid or liquid? Is it homogeneous or marked by particles? Is it brown, black, tan, or chalky white? When you first note the black, crumbly, charcoal looking output, record the time. This marks the completion of the test.


Twelve (12) to eighteen (18) hours is considered a healthy transit time. Too many Americans have a 36-96 hour or longer transit time. Long periods of distress and xenotoxins can allow digestive toxins to be absorbed. Low dietary fiber intake requires the body to work harder to ‘push’ wastes along. The longer the transit time, the greater the possibility that putrefaction lead to unhealthy waste products that are too often reabsorbed and interfere with proper metabolism. The result is predisposition toward or amplification of many chronic intestinal or systemic illnesses. On the other hand, very short transit times may not provide adequate time to digest and assimilated what is eaten. Consult with your physician or nutritional professional to determine the importance of your results for you. It is recommended that the transit time be rechecked twice a month until a healthy transit time is achieved.