ByWALLA! HEALTHJUNE 28, 2026 08:00Fermented foods have existed for thousands of years in almost every culture worldwide, but in recent years they have become the stars of the health world. From yogurt and kefir to kimchi, miso, and sauerkraut, more and more studies point to the connection between these foods and gut health, the immune system, and even the brain.So what actually happens in the body when you add one serving of fermented food to your daily diet?What is fermented food?The fermentation process occurs when "good" bacteria or yeast break down sugars and starches in food. This process not only preserves the food, but also alters its composition and makes many nutritional components more available for absorption in the body.According to nutrition experts, the result is: A food that contains live beneficial bacteria, enzymes, and components that can support the balance of gut bacteria.According to dietitians and physicians, even one serving a day can affect the digestive system within a relatively short time.People who start consuming fermented food on a regular basis often report an improvement in digestion, less bloating, and more regular bowel movements. The reason for this is that the friendly bacteria begin to affect the microbiome, the bacterial population that lives in the gut and influences a wide range of processes in the body.Pickles (credit: SHUTTERSTOCK)Not just digestion: The immune system and the brain are also affectedThe gut microbiome is currently considered one of the most important factors for overall health. Studies point to a connection between the balance of gut bacteria and the immune system, inflammation levels in the body, and even mood.Experts explain that the greater the diversity of bacteria in the gut, the healthier and more resilient the system is considered to be.Why is fermented food sometimes preferable to probiotic supplements? Unlike probiotic supplements that usually contain a limited number of bacterial strains, fermented foods provide a natural combination of live bacteria along with dietary fiber and enzymes.This combination may help the body better absorb nutritional components and support the digestive system in a broader manner.Despite the benefits, experts warn that some people may initially experience bloating or mild discomfort, especially if they were not accustomed to consuming fermented food.Therefore, it is recommended to start with small amounts and gradually incorporate different types into the diet.Which fermented foods should you know?Among the common fermented foods that can be found today in almost every supermarket:Yogurt with active bacteriaKefirSauerkrautKimchiMisoTempehNaturally fermented picklesKombuchaExperts recommend checking the label and choosing products that contain "live bacteria" or those sold under refrigeration, since they are more likely to still contain active cultures.Follow us on Google