What is fructose intolerance?

The term fructose intolerance isn’t very well known despite an ever-growing number of people suffering from it. Many people don’t even know it exists. However, it is related to lactose intolerance. Meanwhile, this is familiar to most people, and alternative products are available in every supermarket. There are even medicines containing lactose that can be taken before meals or drinks. But what is fructose intolerance exactly?

Fructose intolerance is the intolerance of the sugar fructose found in fruits. It is found in almost all fruits, vegetables and cereal products. In particular, fructose is a minimum component of household sugar (sucrose) along with glucose, large quantities of which are found in confectionary products and sugary drinks in particular.
In this article, we at Frusano would like to explain what fructose intolerance is and give clarity about it.

Different forms of fructose intolerance 

There are two different forms of fructose intolerance which differ greatly from one another in terms of cause and symptoms:

  • Type 1: Intestinal fructose intolerance: This form is also known as fructose malabsorption - i.e fruit sugar intolerance - and is the most common form of fructose intolerance. Fructose malabsorption is derived from a defective transport system for fructose in the small intestine.
  • Type 2: Hereditary fructose intolerance (HFI): This form of fructose intolerance involves a very rare fructose metabolic disorder that affects patients from birth. Hereditary fructose intolerance is significantly less common than fructose malabsorption.

Another form of fructose intolerance is sorbitol intolerance. This often accompanies a fructose intolerance. Sorbitol is the sugar alcohol of fructose, which is very closely related to fructose. Sorbitol is found in some fruits and is commonly used as a sweet low-calorie replacement for regular granulated sugar and as a moisturizing agent in baked goods.

Life with a fructose intolerance  

Fructose intolerance is incurable, and no medicine for it has been discovered yet.

Many people with HFI (hereditary fructose intolerance) have a natural aversion to vegetables, fruit and sweet things, which in practice protects them from fructose intake and allows them to live without any significant limitations. But it isn’t like this for everybody. People who haven’t had a fructose intolerance from birth and have enjoyed eating sugary foods up until their diagnosis find it really difficult to have a low-fructose diet or consume no fructose at all.

Unlike type 1 (intestinal fructose intolerance), a low-fructose diet usually isn’t enough to tackle type 2, those affected need a strict fructose-free diet (less than 1g per day) and they need to pay particular attention to their nutrition. This can be a great burden on those affected because, after all, good food and enjoying it is a big part of a good quality of life for many people.

But which products actually contain fructose?

Fructose occurs naturally in almost all vegetable, fruit and grain varieties - no natural foodstuff is completely free from fructose. Their respective fructose content is however extremely varied and can range from a few milligrams to over 40g, such as 100g in honey, for example. In fruits, the fructose content varies greatly depending on ripeness, variety and origin. Many people think that only fruit contains fructose. In fact, the majority of fructose in our food does not come from fruit, but is added to sweeten it. Either in the form of pure fructose or via sucrose.

Fructose is one of the two components of sucrose, which can be found in the majority of our foodstuffs in the form of ordinary household sugar. Even raw sugar, brown sugar and coconut sugar are predominantly made up of sucrose. Almost everything that is sweetened with sugar contains large amounts of fructose, much more than any fruit, whether it’s lemonade, ice-cream, candy or chocolate.
It is practically impossible to gave a completely fructose-free diet when you have a fructose intolerance. What matters is that you try to consume as little fructose as possible and find out your “tolerance threshold”. This can range from 1g per day for those with HFI, to 10g per day for those with a milder form of type 1 fructose intolerance.

You can learn about the fructose content of most foodstuffs in special tables and books with special tables in them, such as "Der kleine Souci Fachmann Kraut", although these values are only averages. However, it is absolutely not possible to have a balanced, low-fructose diet.                             

Reminder: The majority of fructose comes from sweetened food. If you avoid these foods or replace them with fructose-free alternatives, you will eliminate the majority of the fructose. If you avoid fructose-rich fruits such as apples, you will still get enough vitamins. Fruits such as red currants, raspberries and strawberries are relatively low in fructose, and also rhubarb. People with fructose intolerances can also tolerate most pasta, rice, quinoa, pure milk products, meat, fish and eggs. Examples of relatively low-fructose fruits and vegetables are avocados, cucumbers or zucchini. Of course, those with a fructose intolerance should also test out these foodstuffs carefully, as everyone reacts differently.

Sweetness in Frusano’s products.

At Frusano, we sweeten all our products with maltose and grape sugar made from fructose-free glucose syrup. We also produce alternative sweeteners, fructose-free chocolate, jams, all kinds of candy, sweet drinks and much more for people with fructose intolerances. This way, people with fructose intolerances can have also enjoy a normal diet with few limitations. Many of our products are not only fructose-free or low-fructose but also vegan and gluten-free and we ensure there is a low sorbitol content.

In addition, you can find many exciting recipes to inspire people with fructose intolerances and dazzle them with our array of dishes. Hopefully, you will have learned a little bit about fructose intolerance from this post and it has helped you and given you the courage and confidence if you have just received a diagnosis. And be assured: with time, you’ll learn how handle your fructose intolerance!