Fermentation is one of the oldest methods of food preservation — and at the same time one of the most powerful tools for supporting health. Yogurt, kefir, kimchi, miso, natural vinegar, kombucha — all are the result of controlled fermentation with live microorganisms.
But what exactly happens during fermentation and why is it so valuable for our bodies?
What is fermentation?
Fermentation is a biochemical process in which microorganisms — bacteria, yeasts, or fungi — break down sugars and other organic substances in food. As a result, acids, gases, and valuable metabolites are formed, transforming raw food into something entirely different in taste, texture, and nutritional value.
In lactic acid fermentation — which is the basis of yogurt and Onbiome starter cultures — the main product is lactic acid. It is a natural preservative, creates the characteristic sour taste, and maintains an environment in which beneficial bacteria thrive and unwanted ones do not.
Fermented foods and the microbiome
Our microbiome — the community of trillions of microorganisms in the digestive tract — is directly influenced by what we eat. Fermented foods are one of the most direct ways to support it.
Regular consumption of fermented foods is associated with:
- Greater diversity of gut microbiota
- Reduced markers of systemic inflammation
- Better nutrient absorption
- Support for immune function
A study published in Cell (Wastyk et al., 2021) shows that a diet rich in fermented foods increases microbial diversity and reduces 19 inflammatory proteins — results that a high-fibre diet does not achieve to the same degree in the short term.
What do live cultures do in the body?
Live microorganisms in fermented foods don't simply pass through in transit. They interact with the intestinal epithelium, compete with unwanted bacteria for resources, and produce substances — postbiotics — with a direct effect on health.
Among these are:
- Short-chain fatty acids (SCFAs) — nourish the cells of the large intestine and regulate the immune response
- B vitamins and vitamin K2 — synthesised directly by the bacteria
- Enzymes — assist in the breakdown of lactose and other hard-to-digest substances
- Bacteriocins — natural antimicrobial peptides produced by beneficial bacteria
Fermented foods vs. probiotic supplements
Probiotic supplements are a concentrated and standardised way to consume live cultures — particularly useful for specific needs or after antibiotic treatment. Fermented foods, on the other hand, offer something different: a diversity of strains, a prebiotic matrix (the food itself), and postbiotic metabolites — all in one.
The ideal approach for most people is a combination of both: regular consumption of fermented foods as a foundation and targeted intake of a probiotic or synbiotic when needed.
Which fermented foods should we include?
Not all fermented foods are equal. It is important to choose those that contain live and active cultures — pasteurised products lose much of their microbiological value.
Good sources of live fermented foods:
- Homemade yogurt — prepared with a quality BDS-standard starter culture, contains Lactobacillus bulgaricus and Streptococcus thermophilus
- Kefir — rich in diverse strains, including yeasts
- Naturally fermented sauerkraut — without vinegar, only water and salt
- Miso — fermented soybean paste, rich in enzymes
- Natural apple cider vinegar — unpasteurised, with the "mother"
- Homemade fermented drink — prepared with Onbiome starter culture and fresh fruit juice
How to Start?
If you are not accustomed to fermented foods, we recommend gradual introduction — start with small amounts and observe how your body responds. For people with a sensitive stomach or dysbiosis, rapidly increasing intake may cause temporary discomfort.
A good starting point is homemade yogurt — easy to prepare, predictable, and with a proven live culture profile. With a BDS-standard starter culture
For those who want to expand their horizons — the homemade fermented drink with Onbiome is the next step: refreshing, functional, and entirely personalised.
Finally
Fermented foods are not a trend — they are a nutritional practice with a millennia-long history and growing scientific support. Including them in the daily diet is one of the most accessible ways to support the microbiome, immunity, and overall wellbeing.
Start with one. Observe. Add the next. Your body will tell you what works.
