Are fermented foods like kombucha actually good for you?

Humans have been eating fermented foods since ancient times, but researchers are only just beginning to answer some of the biggest questions about the health benefits of fermented foods.

Kefir, kimchi, sauerkraut, and kombucha are all very different foods, but they all have one important thing in common: they’re all fermented foods.

Humans have used fermentation to preserve food throughout history. “Every culture has its own fermented foods,” he says. Gabriel Vinderola“Fermentation is widespread now. There are thousands of different fermentation methods, and it’s being produced in a more industrial way,” says John McCain, an associate professor of microbiology at Argentina’s Universidad Nacional de Litora.

Producing fermented foods on an industrial scale rather than just in the home kitchen has its advantages and disadvantages. Although fermentation eliminates the need for chemical preservatives, researchers at King’s College London recently Nearly one-third of fermented foods contain additives They tested From a UK supermarket.

These additives (salt, sugar, artificial sweeteners, etc.) are within legal guidelines. However, technically some Ultra-processing.

So, are fermented foods actually beneficial for your health, or are they just ultra-processed foods that should be avoided?

Fermented foods are divided into two groups: those that contain live bacteria and those that contain bacteria that are killed during production, such as bread, beer, and wine.

During fermentation, microorganisms typically feed on sugars in food, which fuel all of the microorganisms’ biochemical reactions, Vinderola says.

“This then starts releasing substances that weren’t previously present in the food, such as lactic acid, which has anti-inflammatory properties. It can also break down amino acid chains to release little compounds that are beneficial to the gut.”

Even though fermented foods don’t contain live bacteria, Vinderola says they may still offer some health benefits: Before dying, the microbes produce health-promoting molecules, such as: peptidehe says.

Can fermented foods improve gut health?

The fermentation process can also reduce or remove gluten from some foods, which can be beneficial for people with celiac disease, another gut problem.

In principle, fermented foods could change that: “The main role of fermented foods is to provide live microbes that can get into your gut and train your immune cells how to suppress inflammation,” says Vinderola.

Low-grade inflammation is problematic because inflammatory compounds can spread through the bloodstream and reach the brain, heart and liver, for example. This can lead to chronic conditions, Vinderola says.

Eating more microbes could train the immune system to better distinguish between good and bad bacteria, Cotter says. If the immune system can’t do this well, it could increase the risk of developing autoimmune diseases such as inflammatory bowel disease, he adds.

In a recent study, researchers Eat sauerkraut Raw, shredded, fermented cabbage may have significant anti-inflammatory benefits.

Why? Claudia Stoibert of the University of Leipzig German researchers found that sauerkraut increases levels of lactobacillus bacteria in the bloodstream, which activates a receptor called HCA3, which alerts the immune system to the presence of a foreign substance in the body.

“This means your immune system is less active, which is a good thing,” she says. “A bad immune system can overreact and lead to autoimmune diseases, so it’s good to eat fermented foods to train your immune system to be less responsive.”

Although the research is preliminary, it’s possible that fermented foods may have a positive effect on mental health.

The researchers analysed and compared gut microbiota and other nutrients and found that people who ate fermented foods had a higher bacterial diversity and higher amounts of short-chain fatty acids produced by bacteria than those who did not.

In another small study with the same participants, Gomez and colleagues found that people who regularly consumed fermented foods had more consistent self-reported mental health scores, while those who didn’t experienced more mood swings, although the results have not yet been published.

Gomez is conducting a study (as yet to be published) comparing the effects of organically fermented foods with conventionally fermented foods on the gut. He says he has found an association between fermented food consumption and the neurotransmitter gamma-aminobutyric acid, especially with organic foods.

“It’s a calming inhibitory neurotransmitter and a potential treatment for anxiety and depression,” he says.

In another study, which has yet to be published, Gomez put mice on a Western-style diet high in sugar and fat and ran several experiments to see if the mice developed depression. He then gave half of the mice kombucha and found that their symptoms improved compared to the mice that didn’t eat kombucha, likely due to a change in the microbiome.

Gomez has found that fermented foods Produces metabolites known to be useful in treating obesityAlthough it has been widely studied, the mechanism behind this effect is still unclear, but one explanation is that some of the nutrients in fermented foods may contain metabolites that help regulate appetite via appetite-related neurotransmitters in the body.

As with many areas of health, researchers are now investigating how fermented foods can be personalized to help people with individual health concerns.

“We and other labs are studying specific fermented foods in depth to learn more about how we can further enhance their health benefits,” Cotter says.

“The challenge here is that people making fermented foods at home don’t know what version they have, and it may not be the version that’s right for their particular needs,” he says. “There’s an opportunity to further explore personalized fermentation routes so that we can access the right microbes for specific needs.”

An analysis of fermented foods sold in UK supermarkets by King’s College London found that the nutritional content of different brands of fermented foods varies, but the researchers hope that their study can help improve the nutritional content of commercially available fermented foods.

For example, in the future, a better understanding of what microbes are present in different fermented foods may enable producers of fermented foods to retain these bacteria as they scale up production.

“This has been an issue in the past,” Cotter says. “People ferment foods at home using natural processes, which usually have lots of microorganisms. When you produce them on a large scale, you usually simplify it and only use a few microorganisms for quality control reasons, but in the process, you can lose some of the health benefits.”

Some mass-produced fermented foods, such as pre-made kombucha soft drinks and teas, It is also rich in sugar.The probiotics found in fermented foods can prevent the growth of harmful microorganisms. The risk of food poisoning bacteria remains It is found in unpasteurized foods. For example, contaminated kimchi contains two large E. coli An outbreak occurred in South Korea in 2013 and 2014.

There’s little research on which fermented foods are healthiest, as fermented foods have different bacterial profiles depending on how they’re made.

“Probiotics and prebiotics are specific microbes that can be studied in clinical trials, but we don’t know which microbes are in a particular fermented food,” Vinderola says. “Fermented foods have complex microbial communities that can vary from kombucha to kombucha.”

The most studied fermented food is yogurt, Vinderola says. No matter where in the world it’s made, it’s always made with two specific types of bacteria (Lactobacillus bulgaricus and Streptococcus thermophilusThis makes it easier to build on previous research and form a reliable evidence base.

“But with kefir, for example, you get different results in different parts of the world because it contains different bacteria, so it’s difficult to compare results and build an evidence base,” Vinderola says.

Given these gaps in our knowledge, should we eat more fermented foods? Cotter says yes, but he recommends introducing them into your diet gradually.

“I recommend buying 10 different fermented foods and slowly incorporating them into your diet to see which ones work best for you,” he says, “and keeping a journal of what you eat and how you feel afterward.”

This is because it may take your gut several days to get used to certain fermented foods, which in rare cases may cause a mild allergic reaction.

Gomez found that people who have eaten fermented foods throughout their lives may have lasting health benefits in their gut microbiome, noting that one participant in the study on fermented foods and mental health was from South Korea and the other was from the United States, and that this participant’s gut microbiome was linked to kimchi.

“The American participants probably started eating fermented foods later in life, whereas Koreans are frequent kimchi eaters and the Korean participants probably started eating kimchi from childhood,” Gomez said.

These findings led Gomez to wonder if consuming fermented foods over the long term might have lasting effects.

“But that doesn’t mean you can’t reap the benefits of fermented foods,” he says of people who start eating fermented foods later in life.

Whatever fermented foods you want to try, Vinderola recommends eating them regularly. “Whether you get any health benefits will depend on how often you eat them,” she says. “You should eat them regularly because your immune system needs constant stimulation.”

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