Fermented foods are all the rage. Kimchi, kombucha, sauerkraut and Co. are currently experiencing a real buzz on Instagram and Co. – and apparently not without reason: because fermentation not only makes food sustainable, but also has a positive effect on its ingredients. The fermentation process produces important trace elements and minerals as well as lactic acid, which makes fermented foods have a probiotic effect in the gut.
Study investigates probiotic effects of fermented foods
The probiotic effect in particular is said to be decisive for our well-being – and can even naturally reduce stress. This is shown by new studies from APC Microbiome, a research institute at University College Cork in Ireland. In a study, scientists examined the probiotic effect of fermented foods on the well-being of 45 healthy people between the ages of 18 and 59.
They divided the subjects into two groups, one of which was fed the so-called psychobiotic diet. The control group followed the general dietary recommendations.
The psychobiotic diet is as follows:
- Several servings of fruits and vegetables rich in prebiotic fiber, such as green bananas, cabbage, cereals, legumes
- Fermented foods, such as kefir, kimchi, sauerkraut
After four weeks: less stress, better sleep
Result after only four weeks: the subjects who followed the psychobiotic diet felt less stressed than the control group. They also slept better than before.
The changes lead scientists to the mutual effect of the so-called
gut-brain axis
come back. The gut-brain axis is the connection between the gut and the brain, which is primarily via the vagus nerve in the brain. Through the neural network of the organs, the intestine and the brain communicate using various messenger substances. If there is an imbalance in the intestines, it can have a corresponding effect on overall well-being – simply because 80% of the immune system is in the intestines.
According to the study authors, there was a subtle change in the composition and function of microbes in the gut of the test subjects. “We observed significant changes in the amount of certain key chemicals produced by these gut microbes,” they write in the study.
Fermented foods promote the growth of beneficial gut bacteria
There are a total of about 100 trillion germs in the intestines. Beneficial bacteria sometimes produce vital enzymes, vitamins and amino acids and “filter” harmful substances from the body. Due to their probiotic effect, fermented foods promote the development and maintenance of a healthy intestinal flora with beneficial bacteria. Prebiotics – a special type of dietary fibre, which the test subjects also ingested through their diet, also serve as an energy source for beneficial intestinal bacteria and promote their growth. The interaction of prebiotics and probiotics is therefore elementary for a healthy intestinal environment.
According to the scientists, due to the small number of people tested, further research is needed to test whether the observed effects can also be transferred to the general public. It’s also unclear “whether these results can also be repeated in people with stress-related disorders such as anxiety and depression.”
In any case, it is beneficial for variety in the intestine, digestion and general well-being to regularly include fermented products in the diet. They are even now credited with having an anti-colon cancer effect, and are also said to be able to reduce the symptoms of inflammatory diseases.
Typical fermented foods are:
- Black teas
- sourdough (fermented flour)
- Dairy products containing lactic acid cultures such as yogurt, buttermilk, or kefir
- Sauerkraut
- tempeh
- kombucha
- miso
- Kimchi
- soy sauce and paste
The longer a food ferments, the more organic acids such as lactic acid, trace elements and vitamins are produced. Kimchi or sauerkraut, for example, are rich in vitamin C, beta-carotene and B vitamins. Lactic acid bacteria convert sugar into acid, which not only makes food more durable, but also makes it easier to digest.
See in the video: