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Digestion: How long does it take?By Mayo Clinic staff
Original Article: http://www.mayoclinic.com/health/digestive-system/AN00896
- With Mayo Clinic gastroenterologist
Michael F. Picco, M.D.read biographyclose window
Michael F. Picco, M.D.Michael F. Picco, M.D.
Dr. Michael Picco has been with Mayo Clinic since 1999. He is board certified in internal medicine and gastroenterology. Dr. Picco is an assistant professor of medicine at College of Medicine, Mayo Clinic, and a consultant in gastroenterology at Mayo Clinic in Florida.
He has authored numerous publications in the area of gastroenterology, including original research, editorials and textbook chapters. He works with a team of gastroenterologists that takes care of complex gastrointestinal conditions and has a particular interest in diarrheal illnesses and inflammatory bowel diseases (ulcerative colitis and Crohn's disease). He is also active in medical education in training new gastroenterologist and internists.
"Mayo Clinic's website is an invaluable resource for patients and their families," Dr. Picco said. "Informed patients are better able to participate in their own health care. A patient's participation is vital to the treatment of his or her disease. I hope to assist in helping patients understand their digestive problems and current treatments that are offered. This will allow for better communication between patients, their physicians and other health care professionals."
Dr. Picco serves as a reviewer of new research for several medical journals in the area of gastroenterology and is an active member of the American Gastroenterological Association, American College of Gastroenterology and the Crohn's & Colitis Foundation of America. He serves on numerous committees that address physician training, research and clinical practice in gastroenterology, both at Mayo Clinic and at the national level.
"Patients need to know about their disease, what to expect, the latest treatments and side effects so that they can make informed decisions about their health care. Gastrointestinal disease affects not only patients but also their families. My goal is to assure that our website provides accurate, reliable information and resources for patients. We must always provide the latest, most cutting-edge information to assist patients in dealing with their medical problems," Dr. Picco said.
Digestion: How long does it take?
How long does it take to digest food — from the time you eat it to the time you excrete it?
from Michael F. Picco, M.D.
Digestion time varies between individuals and between men and women. After you eat, it takes about six to eight hours for food to pass through your stomach and small intestine. Food then enters your large intestine (colon) for further digestion, absorption of water and, finally, elimination of undigested food.
In the 1980s, Mayo Clinic researchers measured digestion time in 21 healthy people. Total transit time, from eating to elimination in stool, averaged 53 hours (although that figure is a little overstated, because the markers used by the researchers passed more slowly through the stomach than actual food). The average transit time through just the large intestine (colon) was 40 hours, with significant difference between men and women: 33 hours for men, 47 hours for women.
Two British doctors studied digestion time in children. They fed 35 children juice containing a red marker and asked the children's mothers to note when the stool first turned red. The mean time of transit from mouth to anus for the group was 33 hours (meaning half the children had digestion times slower than this and half had digestion times greater than this).
Metcalf AM, et al. Simplified assessment of segmental colonic transit. Gastroenterology. 1987;92:40.
- Weaver LT, et al. The bowel habits of young children. Archives of Disease in Childhood. 1984;59:649.
- Camilleri M, et al. Relationship between impaired gastric emptying and abnormal gastrointestinal motility. Gastroenterology. 1986;91:94.