An individual with a healthy gastrointestinal (GI) system will process food efficiently. The stomach and small intestine of a healthy individual will digest food in six to eight hours, and pass that food to the large intestine. The large intestine further digests the food, absorbs water and nutrients, and passes the undigested food waste into the rectum. An individual with a healthy GI system typically completes the digestion process in about 24 to 72 hours.
Ben Terrany, MD
- internal medicine
Location and Office HoursShore Gastroenterology Associates
60 NJ Rte 36
West Long Branch, NJ 07764
- Horizon BlueCross BlueShield
- Jersey Shore University Medical Center
- Monmouth Medical Center
- How long does it take a healthy gastrointestinal system to process food?
What is CCK?
Michael Roizen, MD, Internal Medicine, answeredAt the bottom of your stomach and top of your intestines, your food hits an important traffic signal: It's the red light that tells your brain you're full and don't need another large order of onion rings (nor the cheese sauce for dipping or the beer to wash it down).
That red light is delivered by the vagus nerve, which is a large nerve that comes from the brain and stimulates the contraction of the stomach. That vagus nerve is also the main cable controlling the parasympathetic system, which is the relaxation section of your nervous system.
The key stop-sign ingredient here: A peptide produced in your gastrointestinal tract called CCK. Technically, it stands for cholecystokinin, but for our purposes, let's think of it as the Crucial Craving-Killer because its main purpose is to tell your brain that your stomach feels fuller than Dolly Parton's corset.
Without having to go through the chemical pathways of your body (your bloodstream), CCK acts as a very direct message and indicator of your fullness. (Leptin, a hormone that signals fullness, is more of a long-term indicator of your satiety; CCK provides a very short-term, intense message.)
After food spends some time in your stomach, it will slowly leave that reservoir and go into the small intestine via the duodenum, the first part of your intestines that come right after the stomach. That's when CCK (a peptide produced in your gastrointestinal tract) puts up a digestive detour sign—in a very clear physical signal that makes you feel full. It causes the pylorus—the opening at the end of the stomach—to slam shut; that keeps food from moving into the small bowel and that's how your stomach gets full physically—and how you feel full mentally.
One interesting note: High saturated-fat diets lead to less CCK sensitivity, so you do not feel as full as you should after eating a steak.
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Does fructose intolerance affect children differently than adults?
Fructose intolerance can be fatal for children if undiagnosed and untreated. It is often diagnosed when babies start taking formula and baby food, as fructose can be used as a sweetener in these products. Some symptoms of fructose intolerance are the same in both adults and children: vomiting, jaundice (a yellowish discoloration of the whites of the eyes, skin, and mucous membranes), fatigue due to lack of energy, and crankiness. Children may slow down in growth and development. Children and adults both respond well to a fructose-free diet.
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