Why does sugar hurt my stomach

Warning sugar! When the body struggles

Problem case bowel

Bitter for those affected: Only a few doctors seem to be able to track down the sugar problem. Thousands of those affected discuss their needs and worries in internet forums.

Most patients have had a real odyssey with expensive and uncomfortable examinations such as gastroscopy and colonoscopy. A simple breath test for just 40 to 80 euros could give the decisive clue.

When it comes to irritable bowel syndrome, there is always talk of poor nutrition and too much stress. Some people are even put in the psychological corner because the real dimension of sugar intolerance is not properly recognized by doctors.

Often those affected want to cure themselves through a healthy diet and eat a lot of fruit. But that has the opposite effect, because of course there is a lot of fructose in the fruit. And in doing so, those affected could actually get rid of the dangerous intestinal problems with a change in diet that suits them.

Vicious circle in the digestive system

What happens in the intestine when people are intolerant to sugar has now been well researched. The small intestine can only absorb a little or no sugar at all. Fructose, for example, is absorbed from the intestine via special transport systems and ends up in the blood.

If these transport systems fail, fructose intolerance or so-called "fructose malabsorption" occurs: a large part of the fructose reaches the large intestine. Here the bacteria eat the fructose and ferment it. The end products are carbon dioxide, short chain fatty acids and hydrogen.

Carbon dioxide leads to flatulence, the short-chain fatty acids cause diarrhea and irritable bowel symptoms. The small molecule hydrogen enters the bloodstream through the colon wall and is exhaled.

There is also another factor: the more fructose the colon bacteria get, the more they multiply and, through their activity, aggravate digestive problems. A vicious circle.

Because from a certain point the intestine expands so much by the flatulence that the gate between the small intestine and the large intestine no longer closes properly. The contents of the large intestine with its bacteria flow back into the small intestine, which normally has a completely different bacterial environment.

Incorrect colonization occurs: Since the colon bacteria have no place in the small intestine, the small intestine reacts to this attack with an inflammatory reaction.

Since the colon bacteria ferment in the small intestine and form hydrogen in the course of this process, which is exhaled, incorrect colonization can easily be determined with a breath test.

Digestive problems and a bad mood

The patient's symptoms are not limited to gastrointestinal problems alone. Many complain of insomnia and moods up to and including depression. The Innsbruck nutritionist Dr. Prove Maximilian Ledochowski as one of the first scientists.

At the beginning of his research, his position in the professional world was not easy. At first, hardly anyone wanted to believe that the supposedly so healthy fructose can trigger depressive moods.

The mechanism is becoming increasingly clear: fructose influences the metabolism of the protein building blocks, the amino acids. With a fructose intolerance, a certain amino acid, tryptophan, can no longer be absorbed from the intestine. Because the fructose binds the tryptophan to itself and migrates to the large intestine.

This means that this amino acid does not get from the small intestine via the bloodstream to the brain, where it is urgently needed. Tryptophan is the most important building block for the happiness hormone serotonin. If this component is missing, no serotonin can be formed. The result is a bad mood and even depression.

But all industrial sugar

If you suffer from sugar intolerance, it is difficult to avoid it. Because the problematic sugars can be found in almost all industrially manufactured foods today. And not just in the sweet ones, as one might assume.

The milk sugar lactose is in the milk powder. It comes from the surplus production of the European dairy industry and serves as a cheap taste improver and swelling agent. Millions of tons of powdered milk end up in our food every year.

The same goes for whey, which is supposed to be so healthy. It is a by-product of cheese production, a cheap raw material - and rich in lactose.

Corn fructose

The fruit sugar, fructose, is also almost ubiquitous. However, it does not actually come from fruits, but is produced industrially, mostly from corn. The amount of fructose introduced into our food has exploded in the past two decades.

One of the main triggers was the Cuban Missile Crisis in 1962. The United States had difficulties importing sugar cane from Cuba during this period. What was available in large quantities for this was corn. So they turned to the fructose from the maize plant and used it to sweeten the food, which was much cheaper on top of that. This emergency solution has now established itself worldwide.

Our sense of taste has also changed, according to Ledochowski. It has become less sweet and sensitive - worldwide. Not only that all kinds of food are mixed with fructose: Even types of fruit are grown with a higher fructose content. As consumers, we tend to prefer the sweeter apples - some varieties of which today have a significantly higher fructose content than 20 years ago.

For many of us, this oversupply of fructose has become more of a pain than a delight for the palate. In the past it was only around five grams that we ingested daily through our food, today consumption has risen to around 15 grams. For some intestines simply too much of a good thing.