How long does it take to digest food?

How food is digested

The digestive system is made up of the gastrointestinal tract, also known as the digestive tract. This long twisting tube starts at the mouth and ends at the anus. The gastrointestinal tract consists of a series of muscles that work together to breakdown the food you eat.

Let’s take a closer look at how food is digested as it makes its way through the digestive system:

1. The mouth

Digestion begins at the mouth. Once you start chewing and break down food into small enough pieces to be digested, the salivary glands in your mouth secrete saliva. This saliva contains a substance that begins the process of breaking down these food particles into a form your body can absorb and use. That’s why it’s often advised to chew for longer, as this can help to aid digestion.

2. The throat

Once the food passes through your mouth, it enters the pharynx (your throat). From here, it passes on to the oesophagus, which then carries it to the stomach.

3. The oesophagus

The oesophagus is a muscular tube extending from the throat and behind the trachea (windpipe) to the stomach. Food is pushed through the oesophagus to the stomach through a series of contractions.

However, just before the opening to the stomach, there is a ring-shaped muscle, known as the lower oesophageal sphincter (LES). The primary function of the LES is to open to allow food to pass into the stomach and close to keep it there.

4. The stomach

The stomach is a sac-like organ, with strong muscular walls. As well as storing food, the stomach secretes powerful acid and enzymes that help to break down food even further by converting it to a liquid or paste. From here, it then can be moved to the small intestine. 

5. The small intestine

The small intestine is essentially the ‘workhorse’ of digestion, as this is where most nutrients from our food are absorbed into our bloodstream. Any non-liquefiable remnants that are left over are pushed into the large intestine, or the colon.

6. The colon

The colon (large intestine) is a large tube that connects the small intestine to the rectum. Stools that are left over from digestion pass through the colon, where any remaining water is absorbed. The stool is then stored until the colon is emptied through bowel movement, which typically happens once or twice a day.

How long does it take food to be digested?

It can take several hours for our body to digest food. Generally, food stays in the stomach between 40 minutes to two hours, before spending another 40 minutes to two hours in the small bowel. It then spends around five hours in the small intestine, before passing through the colon, which can take anywhere between 10 to 59 hours.

Of course, these are only estimates and how long it actually takes your body to digest food can depend on several factors such as:

• Your body type

• Your metabolism

• The type of food you eat

• Your lifestyle and overall fitness

• If you’re on certain medication

• Your stress levels.

Additionally, certain health conditions, such as irritable bowel syndrome (IBS), gastroparesis and chronic constipation, can also affect how quickly food passes through your gastrointestinal tract.

Digestion and diarrhoea

Diarrhoea can speed up the process of digestion, as you pass more frequent and looser stools than normal. It will affect most people from time to time, and it can be caused by many things, including food allergies, IBS, certain medication, and even anxiety.

Cells in the small intestine or colon lining can become irritated and resultantly, the normal movement of your intestines can become overactive. As a result, the nutrients from the food you eat are passed through the colon too quickly. With less foods being absorbed, this results in loose or watery stool, or what is more commonly referred to as diarrhoea.

Diarrhoea generally isn’t anything to worry about and usually clears up in a few days. If you’re suffering with diarrhoea symptoms, our range of IMODIUM^® tablets and diarrhoea products can help provide relief.

Examples of easy-to-digest foods

To help prevent problems like constipation and IBS symptoms, it’s important to eat the right foods. For example, research suggests that foods that are high in fibre may help prevent constipation. Additionally, high-fibre foods could help to feed the healthy bacteria in your colon and discourage the growth of harmful ones.

Here are some examples of easy to digest foods to consider adding to your diet:

• Fruits and vegetables

• Wholemeal bread

• Brown rice

• Beans

• Oats.

Digestion FAQs

How long does food stay in the stomach?

Food generally stays in your stomach between 40 minutes to two hours. However, this is only an estimate, and it can depend on what type of food you eat. For example, simple carbohydrates, such as rice and pasta, spend an average of 30 to 60 minutes in your stomach. Whereas foods with more protein and fat, such as peanut butter and avocado, can take between two to four hours to leave your stomach. 

How long does it take for the stomach to fully empty after eating?

It usually takes between four and six hours for the stomach to empty after eating. However, for people with certain medical conditions, such as gastroparesis, food can stay in the stomach for longer than it should. You may have gastroparesis if you feel full sooner than normal, are sick, experience tummy pain, heartburn or bloating after eating.

What foods take long to digest?

Foods high in fat like chips and burgers can be hard to digest. Eating these foods can also cause tummy pain and heart burn. Additionally, you may want to avoid spicy foods, as some people may experience tummy troubles from these, including pain, heartburn, and diarrhoea.

What helps digestion after eating?

Drinking lots of water can help waste pass through your digestive system. It can also help to soften your stool. A great way to increase your fluid intake is to drink water with every meal. If you’re not a fan of plain water, try adding a slice of fresh lemon or lime or some sugar-free cordial for flavour.