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Q: How long does the digestion process take in Humans? ( Answered,   0 Comments )
Subject: How long does the digestion process take in Humans?
Category: Health > Fitness and Nutrition
Asked by: anokie-ga
List Price: $5.00
Posted: 22 Jan 2003 09:52 PST
Expires: 21 Feb 2003 09:52 PST
Question ID: 147016
I've been told that the digestion process (from the mouth to the
toilet) takes no less than 17 hours.  This seems off to me.  I'd like
to find out the real answer, and be able to quote medical sources.
Subject: Re: How long does the digestion process take in Humans?
Answered By: tutuzdad-ga on 22 Jan 2003 11:06 PST
Dear anokie-ga;

Thank you for allowing me an opportunity to answer your interesting

I found a reference to this same question, answered by David Ng, PhD
Student, School of Pharmacy and Medical Sciences, University of South


“After putting the yummy stuff into your mouth, it (the bolus) then
has to travel through the entire gastrointestinal tract before coming
out the other end. The gastrointestinal tract for the purposes of this
exercise includes the oral cavity, the oesophagus, stomach, small
intestine, and colon.”

“Food travels down the oesophagus at a rate of approximately 3 to 4
centimetres per second (1 to 2 inches), and the entire process takes
about 5 to 6 seconds. In the stomach, food tends to hang around for a
little longer and this depends on a variety of factors including the
amount of food you have consumed, how much fat it contains, and also
the acidity of the stomach. However, all food should have left the
stomach within 2 to 4 hours.”

“In the small intestine, digestion continues and absorption occurs.
From here on, the time to defecation will vary depending on the time
it takes to adequately digest and absorb in the small intestine. This
will usually take 5 to 6 hours. The "food then enters the colon for
further digestion and water re-absorption before defecation. The time
from it’s entering the colon to defecation is about 12 to 24 hours.”

“Thus, the time for food to travel from one end to the other probably
ranges from about 20 to 30 hours. Although I haven’t had the time to
look further into the rest of your question, I hazard a guess that it
is unlikely that meat will hang around for a week given that the
gastrointestinal tract is very effective in breaking it down with
various enzymes and acidity of the stomach. Foods high in protein and
fats probably would probably take a little longer to pass through than
if it were carbohydrate.”

The bottom line here (no pun intended) is that under normal
circumstances, the complete human digestive process (from consumption
to elimination) takes different amounts of time for different people,
depending on what they eat, how healthy they are, etc. The normal
process takes about 12-24 hours, so 17 hours would be a pretty
accurate estimate if you wanted to depend on the law of averages as
your answer.

I hope you find that that my research exceeds your expectations. If
you have any questions about my research please post a clarification
request prior to rating the answer. I welcome your rating and your
final comments and I look forward to working with you again in the
near future. Thank you for bringing your question to us.

Best regards;





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"How long does it take" digestion

Human digestion

Complete digestive process
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