By Jessica Lewis Updated December 12, 2018
Eating provides your body with the essential nutrients: protein, fats, carbohydrates, water, vitamins and minerals. For your body to make use of these nutrients, they need to be digested and absorbed. The amount of time it takes for food to pass through your digestive tract depends on the type of food you have eaten, among other things.
In general, it can take 24 to 44 hours from the time you eat food to the time it leaves your body as waste. The amount of food you eat and whether it is solid or liquid will affect how long it takes to pass from the stomach to the small intestine and from there to your colon.
The chemical makeup of the food, as well as how well you chew it, can also affect how long it takes for food to reach your small intestine. More time is needed in the stomach if the food is still in relatively large pieces.
Digestion begins in your mouth, with saliva coating food and beginning the process of braking it down. In the stomach, the food is mixed with strong stomach acids for two to four hours and breaks down from large molecules into small ones and move along to the small intestine. Some of the molecules are absorbed through the small that then move on to the small intestine.
The small intestine, also known as the small bowel, is where digestive juices from your liver and pancreas mix with food to break it down into usable nutrients. It is also responsible for absorbing these nutrients from the food you eat. Over 20 feet in length, the small intestine also delivers the leftovers that aren't absorbed -- the waste -- to your colon, upward of 1 liter per day. Given a standard diet and a healthy gut, it can take 2.5 to 3 hours to empty half of your small intestine, or it can take longer than 10 hours.
The large bowel, including the cecum, colon and rectum, is more muscular than the small intestine and is between 5 and 6 feet long. The primary job of the colon is to absorb any remaining nutrients and to push undigested food and waste through to your rectum to be expelled. It also absorbs water, changing the waste product from a liquid mush to a firmer stool that's easier to pass. It takes 7 to 16 hours to absorb all of the necessary fluid. Overall, it can take between 30 and 40 hours for food to fully pass through your colon, assuming a healthy diet and no constipation.
To speed up the passage of waste through your colon, you can increase the amount of insoluble fiber you consume. Insoluble fiber passes through your digestive system intact and is found in whole grains, vegetables and legumes. The recommended intake is 25 to 38 grams of total fiber per day, both soluble and insoluble, although most Americans do not meet this amount. If you do increase your dietary fiber intake, do so gradually, as too much too soon can cause gas or diarrhea as your digestive tract is unused to handling the extra fiber.
Medically reviewed by Natalie Butler, R.D., L.D. — Written by Jayne Leonard on October 1, 2017
Digestion is a process where the body breaks down food into smaller particles to absorb them into the bloodstream.
Complete digestion of food takes anywhere between 24 to 72 hours and depends on several factors, including the type of food eaten and the presence of digestive issues.
This article looks at the digestive process and potential digestive problems and recommends ways to improve digestion.
Share on PinterestOn average, food takes 6 to 8 hours to pass from the stomach and small intestine to the large intestine. From there, it may take over a day to digest further.
In many cases, the food moves through the stomach and small intestine within 6 to 8 hours. It then passes to the large intestine (colon).
However, the exact time varies and depends on factors such as:
- Amount and type of food eaten: Protein-rich foods and fatty foods, such as meat and fish, can take longer to digest than high-fiber foods, such as fruits and vegetables. Sweets, such as candy, crackers, and pastries, are among the fastest foods digested.
- Gender: A 1980s study found that the transit time through the large intestine alone was 47 hours for women and just 33 hours for men.
- The presence of digestive issues: Crohn’s disease, diverticulitis, and irritable bowel syndrome are some of the conditions that may slow down digestion.
Once food reaches the large intestine, it may remain there for up to a day or more as it undergoes further breakdown.
It’s a commonly held belief that digestion only takes place in the stomach. In fact, there are three separate stages of digestion:
Oral stage of digestion
Chewing food breaks it down into smaller particles and mixes them with saliva. An enzyme present in saliva, called amylase, acts on carbohydrates in the food to break them down. The food particles can then form a soft mass that’s easy to swallow, known as a bolus.
Gastric stage of digestion
In the stomach, an enzyme called pepsin helps to break down proteins into smaller particles. Stomach acid also plays an important role in preventing food-borne illness as it kills any bacteria or viruses that may have been present in the food.
Intestinal stage of digestion
Nutrients and water that have been removed from the digested food pass through the walls of the small intestine. They enter the bloodstream and travel to various areas of the body where they are used to repair and build.
The unabsorbed and undigested food that remains then moves to the large intestine. Here, some more nutrients and water are absorbed. The remainder is stored in the rectum until it leaves the body through a bowel movement.
To enjoy a healthy digestive system and to prevent constipation and diarrhea, try the following:
Eat a balanced diet
Share on PinterestPlant foods that are sources of fibre, including apples, legumes, and whole grains, may aid healthy digestion.
Fiber-rich foods, including fruits, vegetables, legumes, and whole grains, help move food through the digestive system more rapidly. They also help prevent constipation, feed gut bacteria, and help with weight loss.
Meat, particularly red meat, is hard to digest so should be eaten sparingly.
Processed and fast foods are often high in fat, making them difficult to digest. They are also rich in sugar, which may upset the balance of bacteria in the gut.
These types of food also contain additives that can cause stomach upset in some people and contribute to poor health.
Stay hydrated
Drinking enough water and other liquids, such as teas and juices, can prevent constipation and keep food moving through the digestive system.
Take probiotics
Probiotics are beneficial bacteria that help restore the balance of bacteria in the body by reducing the growth of harmful bacteria in the gut. The following foods are rich in probiotics:
- natural yogurt
- kefir
- sauerkraut
- kimchi
- miso
- fermented vegetables
Probiotics are also available in supplement form.
Make sure to include fiber-rich and prebiotic-rich foods to feed the probiotics you ingest as well as the healthy bacteria already in your colon.
Regular physical activity
Engaging in daily exercise benefits the digestive tract, as well as the rest of the body. Some people find that a gentle walk after meals reduces bloating, gas, and constipation.
Stress management
Being stressed can slow down digestion and contribute to symptoms such as heartburn, cramping and bloating. To reduce stress levels, engage in meditation, deep breathing exercises, and yoga. Even a few simple deep breaths before you eat can help. It is also important to get enough sleep every night to reduce stress and aid digestion.
Dental hygiene
As digestion begins with chewing in the mouth, problems with the teeth can interfere with this important step. Older adults, in particular, can be affected by improper chewing techniques due to dental issues. Brush and floss the teeth daily, and visit a dentist regularly.
Digestive enzymes
People with low stomach acid, chronic stress, digestive diseases and other conditions may benefit from taking supplements containing digestive enzymes. While these are freely available from health stores, it can be helpful to discuss enzyme supplementation with a doctor first.
Manage digestive conditions
Several medical conditions can cause problems with digestion. People with these conditions should always work with their doctor to manage their symptoms and reduce digestive distress.
Share on PinterestSuffering from gastro‐esophageal reflux disease, or GERD, may affect digestion. If digestive problems are persistent, a doctor should be consulted.
Possible digestive problems include:
These conditions can cause issues with digestion, and contribute to symptoms such as heartburn, bloating, constipation, and diarrhea.
Those who regularly experience symptoms of poor digestion, such as gas, bloating, constipation, heartburn, or diarrhea, should see a doctor who can rule out any serious conditions.
If anyone experiences any of the following symptoms, they should see a doctor immediately:
- rectal bleeding
- significant weight loss
- fever
- persistent vomiting
- feelings of food blockages in the food pipe
Digestive symptoms that get progressively worse or change abruptly also require medical attention.
The time it takes to digest food varies between 24 and 72 hours and depends on several factors. To enjoy optimal digestion, eat a balanced, high-fiber diet, engage in regular exercise, reduce stress, and manage any digestive conditions that may be present.
If symptoms of digestive distress are severe, persistent, or change over time, it is important to see a doctor.
Last medically reviewed on October 1, 2017
- GastroIntestinal / Gastroenterology
- Nutrition / Diet