How Long Does It Take to Digest Food

Have you ever wondered what happens to your food after you ingest it? I did. After a little study, I found I could now make a map of the whole process. It’s pretty fascinating.

Digestion is not the same from person to person. Everyone digests their food a little differently. Some people have a higher metabolism rate, while others have a lower one. Just like snakes, some people can take a long time to digest what they’ve eaten. Others have a fast belly movement. Why is that and how does it happens? Let’s find out.

What Is Digestion

First thing to know is that digestion does not only occur in your belly. It starts in the mouth. By definition, digestion is the process that decomposes food into smaller and then even smaller substances, until those substances are small enough to be absorbed through the small intestine and the large intestine into your body.

The gastrointestinal tract, where digestion occurs, starts in the mouth and ends at the anus. It measures about 9 meters in length.

Stages of Digestion

Digestion is a two-step process. The two main stages include mechanical digestion and chemical digestion.

It All Begins In Your Mouth

Digestion begins in your mouth where your teeth grind the food into small chunks and mix it with saliva. 

Saliva contains:

  • enzymes that break down the starch, fats, and protein in food
  • mucus to lubricate the food and make it easier to slide down your throat
  • hydrogen carbonate which keeps the mouth’s pH alkaline

Down Into the Stomach

The chewed food is then swallowed, which puts it into the esophagus. The food is transported, through muscular movements, down the throat. These waving movements push the chewed bolus (rounded mass) of food into the stomach.

In the stomach, what you’ve swallowed is met by the gastric juices that contain hydrochloric acid and pepsin, which are very corrosive and are meant to extract the proteins from food. At the same time, your stomach secrets a mucus to protect its wall from these corrosive acids. This way, only the food will be affected and transformed by these strong acids.

The muscular contractions (called peristalsis) continue in the stomach, mixing the food with the digestive enzymes. This whole process of digestion lasts for about 1-3 hours in the stomach.

Further On … Into the Small Intestine

When the solid food has become a thick, viscous liquid into your stomach, the pyloric sphincter opens, and this liquid slowly goes into your duodenum. Here, other digestive enzymes (secreted by the pancreas) and bile juice (secreted by the liver) come into action and mix with it.

All this mixture advances towards the small intestine, where the food continues to be digested, the term used when what you’ve eaten is converted into useful substances. While this partially digested liquid food becomes further digested in the small intestine, the process of absorption of nutrients, minerals, vitamins, amino acids, fatty acids, and sugars into the lymphatic system begins. Some of these are reabsorbed into the blood through the walls of the large intestine (colon).

This process lasts between 6 to 8 hours.

A Long And Winding Road – The Large Intestine

By now, the semi-liquid food, mostly depleted of nutrients, has transformed into a semi-solid matter called feces. This travels into the large intestine.  The digested food can remain in the large intestine between 12 to 47 hours until it builds up to the point that it is expelled out of the body with a bowel movement.

This is how digestion finally ends.

It all lasts, more or less, about 50 hours. One study said 53 hours was the average, but the markers in that study were said to pass through the body quicker than the food. Therefore, the average was more like 33 hours for men and 47  hours for women.

6 Factors That Influence the Digestion Process

  • The type of food you eat – some foods are easier to digest (juices, fruits, vegetables), while others take longer to process (meat, pasta, pastry, beans, processed food, fried food).
  • The quantity of food – of course, smaller portions are easier to digest than larger ones.
  • Gender – it seems that generally, men digest food faster than women.
  • Metabolism – some people have an accelerated metabolism rate, while others a slower one.
  • Digestive problems – diseases of the gastrointestinal tract, such as irritable bowel syndrome, gastritis, lactose intolerance, etc. may slow down digestion.
  • Other health problems – may contribute to a slower digestion.

9 Practical and Effective Steps to Improve Digestion

  1. Eat more foods that are a great source of fibers, such as fruits, vegetables, and whole grains, as these speed up the intestinal movement.
  2. Avoid and even eliminate heavily processed, fried, greasy food.
  3. Eat smaller portions and avoid overeating. This can reduce the digestion period by half.
  4. Chew your food slowly and many times (about 30 times) before you swallow it because this will help it break down easily inside your stomach and intestines.
  5. Eat at regular hours – a chaotic lifestyle and eating habits lead to poor digestion patterns. That is why it’s important to schedule your meals at regular hours, at the same time every day.
  6. Use intermittent fasting, pausing eating for 8 to 12 hours, to accelerate your metabolism and allow your digestive system to rest.
  7. Drink enough water – Water helps you eliminate toxins out of the body, boosts digestion, makes you feel full, helps you reduce the amount of food you eat, improves sleep, and even eliminates sugar cravings.
  8. Consume probiotics, such as yogurt, kefir, sauerkraut, kimchi to maintain a healthy gut flora.
  9. Activity helps. Move your body daily through simple physical exercises, dance, fitness, jogging, or even walking (for 15-30 minutes). Activity helps your digestion, improves your metabolism, boosts immunity and muscular tone. It even stimulate your brain (which will then remind you to stay active).
  10. Sleep well – a good sleep during the night will help your body rest, regenerate, and will improve metabolism.
  11. Don’t worry, be happy – Stress contributes to poor health, while a happy mood and emotional balance improve health and digestion.