![[Report Bild]](/static/reportImages/fruktose.jpg)
What is fructose?
Fructose (fruit sugar) belongs to the group of carbohydrates and, like glucose, is a simple sugar. It is mainly found in fruit and some vegetables and, together with glucose, forms our household sugar (sucrose).
Fructose intolerance is a disorder in the utilization of fructose. A distinction is made between two forms:
- Fructose malabsorption: Fructose cannot be adequately absorbed in the small intestine. This leads to flatulence and diarrhea.
- Inherited (hereditary) fructose intolerance: This form is extremely rare and is attributed to a congenital enzyme defect that blocks the breakdown of fructose in the liver. The fructose accumulates in the liver and this can lead to kidney and liver damage. Hereditary fructose intolerance is recognized in babies when they are first fed fruit and vegetables. The treatment is strict avoidance of fructose.
Examples of foods high in fructose:
| Food | Amount of fructose per 100g food |
|---|---|
| Fruit (e.g. apples) | 7.3 g |
| Fruit juice (e.g. apple juice) | 6.4 g |
| Fruit jams | ~20 g |
| Dried fruit (e.g. apple) | 28 g |
| Honey | 38 g |
| Baked goods (e.g. nut stollen) | 1.2 g |
| Confectionery (e.g. Smarties) | 0.5 g |
| ice cream | 0.7 g |
| Chocolate muesli | 1.5 g |
| Fruit yogurt, ready-made products | 0.3 g |
Good to know
Avoiding fruit and certain vegetables can quickly lead to a vitamin deficiency. We therefore recommend the use of food supplements that ensure the basic requirement of vital substances. People with congenital fructose intolerance can achieve a very good quality of life, provided they stick to a fructose-free diet. Otherwise, symptoms such as hypoglycemia, vomiting, fatigue, neurological disorders or even seizures can occur. Typically, those affected develop an aversion to fruit in early childhood.
What does it mean to be fructose intolerant?
Hereditary fructose intolerance is caused by a rare genetic defect. This causes a deficiency of an enzyme that is required for the breakdown of fructose in the body and thus causes a disorder of carbohydrate metabolism.
It is estimated that 1 in 20,000 to 60,000 people worldwide suffer from hereditary fructose intolerance. Fructose is a component of most fruits and vegetables, and is also part of sucrose (also known as household sugar or granulated sugar), which is why it cannot be metabolized properly in some cases. Ingesting even a tiny amount of fructose can then lead to low blood sugar levels. Possible signs of inherited fructose intolerance include
- vomiting
- flatulence
- tiredness
- heartburn
- abdominal cramps
If this disease remains undetected, it leads to kidney and liver damage and can have a severe course.