Kombucha, kefir, ayran: which of these really supports the microbiome (a scientific view without idealization)

Світлана Бурмей
1 day ago
7 min read

The Age of Fermentation and the Illusion of a Universal Panacea

In recent years, the health food industry has been experiencing a real boom in fermented beverages. Supermarket shelves are full of various bottles of kombucha, craft kefir and ayran, which marketers position as a universal elixir for digestive health. We are promised an instant improvement in immunity, perfect digestion and detoxification. However, modern 4P medicine (personalized, predictive, preventive, patient-centered) and in-depth molecular and genetic studies of the microbiome prove that the reality is much more complicated.

Our gastrointestinal tract is not just a reservoir for digesting food, it is a huge "superorgan" inhabited by trillions of microorganisms. And these bacteria have their own needs, their own circadian rhythms and a unique, genetically determined species composition (enterotype). Scientists warn: "blind" consumption of fermented foods without understanding the individual state of the microbiome may not only not bring benefits, but also seriously harm. The same microorganism in one person's body can act as a healer, and in another's body - as a provocateur of inflammation. In this article, we will analyze popular fermented drinks - kombucha, kefir and ayran - from a scientific point of view and find out which of them really supports the intestinal ecosystem, and which is just a marketing myth.

Kefir for the Gut: The Scientific Basis and Hidden Risks

Historically, fermented milk products were the first to come under the close attention of microbiologists. Ilya Mechnikov even proved the benefits of lactic acid bacteria for longevity. Modern research confirms that fermented products such as yogurt and kefir contain prebiotics, probiotics and postbiotics (beneficial metabolites) that can reduce the number of undesirable opportunistic microorganisms in the intestines.

In particular, specific strains found in kefir fungi, such as Lactobacillus kefiranofaciens M1 , have been clinically proven to have potent anti-inflammatory effects and can alleviate symptoms of experimental colitis. Therefore, kefir for the intestines can indeed be an excellent source of lactobacilli that produce lactic acid, acidify the colonic environment, and thereby create unbearable conditions for putrefactive bacteria.

However, here lies the main problem: individual tolerance of milk sugar (lactose) and casein. Even if you do not have genetic lactase deficiency, your microbiome may not be ready for such a product. According to research by the Ukrainian biotechnology company Ediens, the reaction to milk depends entirely on your enterotype. If your intestines are dominated by bacteria of the genus Ruminococcus , and there is a lack of mucin-degrading bacteria (for example, Akkermansia ), dairy products will not be digested, but will begin to ferment aggressively. As a result, instead of lightness, you will get acute bloating, flatulence and systemic inflammation of the intestinal walls. Therefore, kefir is useful only for those whose microbial ecosystem is able to adequately metabolize it.

Kombucha benefits or a sugar trap for the microbiome?

Kombucha is experiencing a renaissance these days. This drink is made by fermenting sweetened tea with a symbiotic culture of bacteria and yeast (SCOBY). Advertisements claim that kombucha, whose benefits are supposedly endless, is the best source of antioxidants, organic acids (acetic, gluconic), and live probiotics. Indeed, the organic acids in quality homemade kombucha can inhibit some pathogens.

But let's look at it through the lens of evidence-based 4P medicine. Commercial kombucha sold in stores has two critical drawbacks:

High content of added sugar (or sugar substitutes). To make the drink tasty, manufacturers add huge doses of sugar or syrups to it. As microbiologists note, sugar and artificial sweeteners rapidly increase glucose levels and stimulate the growth of undesirable species of enterobacteria in the intestinal microbiome. Excess carbohydrates instantly become food for yeast fungi (in particular Candida albicans ), the critical growth of which is a direct sign of a violation of the intestinal protective barrier.
Uncontrolled symbiosis. Unlike evidence-based pharmabiotics, where bacterial strains are genetically sequenced and calibrated to the milligram, kombucha contains a “wild,” uncontrolled set of microorganisms. If a person already has dysbiosis, bacterial overgrowth syndrome (BOS), or inflammation, introducing an additional army of wild yeast and bacteria will cause a real microbial “war”. Pathogens and yeast will begin to ferment the sugars in the kombucha, releasing toxic gases and alcohols, which will only increase bloating, nausea, and the so-called toxic “head fog.”

Ayran and the Microbiome: A Salty Alternative

Ayran is a traditional fermented milk drink of Turkic and Caucasian peoples, consisting of sour milk (katyk), water and salt. Due to the process of double fermentation (lactic and alcoholic), it has a refreshing taste and contains less lactose than regular milk or kefir.

How do ayran and the microbiome interact ? On the one hand, ayran has obvious advantages over sweet yogurts or industrial kombucha. The absence of added sugar makes it safer for people prone to candidiasis. The presence of salt helps restore water and electrolyte balance, which is especially important in the summer heat or after physical exertion. The bacteria Lactobacillus bulgaricus and Streptococcus thermophilus , which are usually used to ferment katyk, secrete lactic acid, which acts as a mild antiseptic in the stomach.

However, as in the case of kefir, ayran remains a dairy product. If the barrier function of your intestines is impaired (leaky gut syndrome), or if you have a predominance of microorganisms prone to putrefactive processes on the background of animal proteins, ayran will not become a medicine. Moreover, excessive salt consumption can disrupt the osmotic balance of the mucous membranes.

The Trap of "Blind" Fermentation: Why Not Everything Healthy Has to Be High

The main mistake of the modern nutritional approach is that people try to "pour" as many beneficial bacteria into themselves as possible, consuming liters of kombucha and kefir. However, there is a golden rule in microbiology: health is balance. High biodiversity (Shannon index) is a marker of the body's resilience. But, as experts from Ediens emphasize, even if we see excessive growth of objectively beneficial bacteria (for example, bifidobacteria), this is also an imbalance. "Not everything useful should be high... If we are oversaturated, accordingly, we are also imbalanced."

When you drink fermented beverages uncontrollably, you are wreaking havoc on the ecosystem. We must not forget that a person’s own, native commensal bacteria, which are developed and live with them their entire lives, are much more valuable and effective than any transient microbes from kefir or kombucha. Fermented beverages are a great addition to a healthy diet for a healthy person, but they are not able to cure a sick microbiome. They will not replace the need to feed your native flora with high-quality fiber.

Evidence-Based 4P Medicine: From Casual Drinks to Biohacking

In order not to play "roulette" with your digestion, sorting through kombucha, kefir and ayran, it is worth turning to scientifically based correction methods. Ukrainian biotechnology company Ediens offers a comprehensive approach based on 37 years of scientific research:

1. Molecular Genetic Analysis (NGS) : Instead of guessing whether kefir is right for you, science allows you to do a precise analysis of your gut microbiome. This analysis reveals your enterotype, species balance, Firmicutes/Bacteroidetes ratio (which is responsible for the tendency to gain weight), and the presence of opportunistic bacteria. Only with this "map" can you understand what your body is really lacking.

2. Personalized Nutrition Plan : Based on the genetic data and metabolomic profile, a powerful mathematical IT algorithm creates your personalized nutrition plan. The program will accurately calculate whether kefir or fermented foods will be a medicine for your bacteria, or, conversely, will provoke inflammation and fermentation.

3. Targeted correction with pharmabiotics: If the analysis reveals serious dysbiosis, regular kefir will not cope with pathogens. In such cases, it is necessary to use clinically proven new-generation pharmabiotics. For example, the niche biopreparation “ My Second Brain. Intestinal Microbiome ” (available in convenient sachets) contains high concentrations of unique live strains of lactobacilli. It purposefully and without conflict suppresses putrefactive and gas-forming flora, treats irritable bowel syndrome, restores the mucous membrane and eliminates heaviness, flatulence or constipation. And to enhance the prebiotic effect, Ediens offers an innovative product — “ First Microbiome Salad ” (jointly with TM “Zelenyok”), where live starter bacteria are instantly activated in the salad, ensuring perfect digestion of fiber without the slightest bloating.

Conclusion

Kombucha, kefir, and ayran are popular fermented foods that can be beneficial for maintaining your microbiome, but only if they are perfectly compatible with your individual enterotype. Kefir is a source of lactobacilli, but can cause bloating due to lactose and the specifics of your microflora. Kombucha carries a serious risk due to its high sugar content, which "feeds" Candida fungi and causes fermentation. Ayran is a good salty alternative without sugar, but it is still a dairy product that is not suitable for everyone. Modern 4P medicine proves: there are no universally useful products. Instead of idealizing random drinks from the mass market, it is worth examining your microbiome genetically and correcting it with the help of personalized nutrition and evidence-based pharmabiotics from Ediens. Only such an approach guarantees true health, ease, and active longevity.

Short questions and answers (Q&A)

1. Is the kombucha, whose benefits are so advertised, really ideal for the microbiome? Answer: Not always. Industrial kombucha often contains a lot of added sugar. If you already have an imbalance of microflora (an excess of opportunistic bacteria or Candida fungi ), this sugar will become “fuel” for them. Pathogens will begin to multiply rapidly and ferment sugars, which will inevitably lead to acute flatulence (bloating), pain and support chronic inflammation in the intestines.

2. Why does gut kefir improve digestion in some people and cause bloating in others? Answer: It all depends on your individual microbiome profile (enterotype). Kefir contains beneficial lactobacilli and postbiotics. But if your gut is dominated by specific bacteria (such as the Ruminococcus genus ) and lacking mucin-degrading bacteria, they will aggressively ferment the milk instead of digesting it properly. This causes gas and discomfort.

3. What is better to choose in the summer: are ayran and microbiome compatible better than microbiome and sweet drinks? Answer: Yes, ayran is a much safer alternative to sweet yogurts or industrial kombucha. It does not contain added sugar, which reduces the risk of rapid reproduction of pathogenic fermentation flora. In addition, ayran's lactic acid bacteria and salt help maintain acid-base and electrolyte balance. However, it remains a dairy product, so it requires individual tolerance.

4. What to do if fermented drinks cause discomfort, but the microbiome needs to be restored? Answer: In this case, you should abandon the "blind" use of products and turn to 4P medicine. Ediens offers a genetic analysis of the microbiome to develop a personalized nutrition plan (Ediens Nutree). To quickly eliminate gases, inflammation and dysbiosis, the niche pharmabiotic "My Second Brain. Intestinal Microbiome" is used , the clinically proven strains of which are guaranteed to safely and reliably restore intestinal health.