A woman sitting on her bed, suffering pain from maldigestion, right after she got up.

Maldigestion – A common disorder in the digestive process

Maldigestion is often also described by the general term of "food intolerance". This is what happens when the body does not properly break down the food into its components, due to missing enzymes. As a result, the nutrients can be digested in an alternative way, e.g. by intestinal bacteria which may lead to different symptoms. Additionally, in the worst cases, only a few nutrients can be provided to the organism in adequate quantities (malabsorption) which might lead to deficiency symptoms occurring.

Many patients with food intolerances also suffer from unpleasant symptoms such as nausea, abdominal cramps and pain as well as diarrhoea and fatty stools. It is estimated that more than 20% of the population in industrialised countries suffer from food intolerances.

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What types of food intolerances are there?

A distinction is made between allergic intolerances and the much larger group of non-allergic intolerances, in which the digestive enzymes are missing. There are also structurally caused food intolerances that occur due to an enzyme deficit caused by an organic disease, for example, pancreatic insufficiency. The most common non-allergic functional intolerance is lactose intolerance. It occurs when people poorly digest lactose, a type of sugar find in dairy products, due to a lactase enzyme deficiency in the small intestine.

What happens during a "normal" digestive process?

For a better understanding of what "goes wrong" with maldigestion, it is worth taking a quick look at healthy digestion: it essentially breaks down food into its components in two ways. Mechanically (for example by chewing and by gastrointestinal movements) and chemically and enzymatically by stomach acid and enzymes. The different nutrients, minerals and vitamins are then absorbed to the bloodstream by the intestinal wall, from where they supply the entire organism.

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How does maldigestion develop?

Many organs are involved in the digestive process to ensure that our body receives all the nutrients, vitamins and minerals it needs. Intolerance can arise based primarily on two factors:

  • Intolerance based on food allergies: Intolerance can result from food allergies (for example to nuts, fish, soy products). In addition to gastrointestinal problems, it can also lead to other allergic reactions such as flashes, rashes and shortness of breath.
  • Intolerance based on enzyme deficiency: This intolerance results as certain foods cannot be broken down because there are insufficient suitable enzymes available.
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Where can maldigestion occur?

Maldigestion due to Pancreatic insufficiency

The pancreatic enzymes break down the carbohydrates, proteins and fats in the food chime as soon as it is in the small intestine. The production or release of these enzymes can be impaired for various reasons, such as after surgery, inflammation of the organ, or other pancreatic diseases.

Maldigestion due to impaired biliary function

Another important digestive function is performed by bile. It is produced in the liver and stored in the gallbladder. It helps to break down and absorb fats from food. If the production or release is disturbed, some of the fats are excreted undigested and the so-called fatty stool occurs. This can be caused, for example, by gallstones, hepatitis or other diseases of the organ.

Maldigestion in the intestine

In the small intestine, the food is further reduced in size by muscle contractions and decomposed with the help of further enzymes. Some diseases of the intestine may also lead as a consequence of the underlying inflammation to reduced enzymes, such as enteritis or Chron's disease.

Coeliac disease is also one of the diseases that can take a severe course if undetected. It mainly affects the intestine and is caused by a reaction to gluten, a group of proteins found in certain grains. It has both allergy and autoimmune characteristics. Gluten-containing foods cause inflammation of the mucous membrane of the small intestine, which can be accompanied by destruction of the intestinal epithelial cells. As a result, nutrients are less easily absorbed, which can lead to serious deficiency symptoms. The symptoms and the severity of the clinical picture can be very different. Possible signs are among others diarrhoea, flatulence, fatty stool, loss of appetite and weight, nausea, fatigue. However, the disease can often go undetected for a long time. A therapy is currently not possible, only a lifelong abstention of gluten-containing foods helps.

Other serious diseases of the gastrointestinal tract can - but do not have to - be at the root of maldigestion. Therefore, please always consult a physician if the symptoms persist or recur for a longer period of time. They can find out with certainty where your complaints come from. Only when the diagnosis has been made, do therapeutic measures make sense.

Carbohydrate maldigestion

Carbohydrates, like lactose (milk sugar) and fructose (fruit sugar), are some of the nutrients that provide the most calories in our diet. But if those aren’t correctly digested in the small intestine, it’s not only our calorie intake that may suffer. The sugars reach our colon undigested, where they will be fermented by bacteria as they pass the large intestine. The produced gas has been linked to an increased occurrence of functional digestive symptoms, including bloating, flatulence or abdominal pain.

Lactose or fructose maldigestion can also occur as a symptom of other diseases, like the already mentioned pancreatic insufficiency, Crohn’s or celiac disease, as a consequence of surgical intervention or simply as a result of getting older. Even though some people are born with a lactase (the enzyme responsible for breaking down milk sugars) deficiency, quite often it’s the natural process of ageing that decreases its efficiency. This can be combated either by the consumption of lactase preparations or by diet modifications that reduce lactose intake.

The lack of enzymes that help digest fructose - sucrase and maltase - can also be responsible for the occurrence of maldigestion symptoms – but often it may not be due to a reduction in enzyme activity, but more likely due to an excessive fructose intake in the first place. Human intestines can process only a limited amount of these sugars before they start fermenting in the colon. Similarly, to lactose maldigestion, there are supplements available to combat the symptoms.

How does a maldigestion show up?

The range of symptoms of intolerance and/or malabsorption is diverse.

Possible symptoms of maldigestion include:

  • Nausea - sometimes even vomiting
  • Bloating
  • Abdominal cramps
  • Abdominal pain
  • Diarrhoea and/or constipation
  • Flatulence
  • Steatorrhea, also known as fatty stool (voluminous, clay-coloured, foamy stool with a penetrating smell)
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How are incompatibilities tested?

If you think you have an intolerance you should first observe your body yourself for a while - preferably with a diet and symptom diary. Then your doctor can conduct a medical history interview with you and, if necessary, use other diagnostic procedures beforehand to rule out other causes.

If there is a suspicion of intolerance, there are many proven test procedures, for example:

  • Breath test (e.g. in case of suspected lactose or fructose intolerance)
  • Blood test (e.g. if coeliac disease or histamine intolerance is suspected)
  • Urine and stool tests

What therapies are available?

The therapy approaches are as varied as the causes. If the underlying disease is an organic one, the first treatment aim is – of course – to treat the underlying cause. Usually, the symptoms will improve then.

In general, a diet can help with functional food intolerances. Avoid the foods, which are not digested properly or which you are allergic to. There are moderate diets in which the trigger is only reduced (for example in the case of acquired fructose intolerance) and strict diets that require the complete elimination of the "irritant". Sometimes it is also possible to supply missing enzymes from the outside. This is possible, for example, with lactose intolerance.

If maldigestion, allergies or other diseases can be ruled out by a physician as the cause of your symptoms, you may suffer from a functional gastrointestinal disorder such as irritable bowel or functional dyspepsia. In this case, a mixture of effective herbs can help balance the muscles in the gastrointestinal tract and calm irritated gastric nerves. Many sufferers use Iberogast®, an oral liquid that contains nine perfectly matched herbs and has already helped over 80 million people around the globe with problems such as stomach pain, nausea or bloating.

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