Natural Probiotics: 8 Best Food Sources

Although there is currently no such thing as a recommended daily intake of probiotic cultures, there is consensus among experts that their regular intake in the diet has a positive effect on the human body.

In addition to dietary supplements, probiotics can also be found in some common foods. We have prepared for you a selection of the richest natural sources of probiotics, which can often be equal in content to probiotics from pharmacies.

Probiotic microorganisms have been proven to affect the human organism

Although the idea of ​​the functioning of intestinal microflora was first expressed by the French-Russian scientist Ilya Ilyich Metchnikoff, the term probiotic first appeared almost 60 years later in 1965 , where it was even used in a slightly different meaning. Since then, the definition has changed several times, until  in 2001 a definition describing probiotics as

“… living microorganisms that, when administered in adequate amounts, confer health benefits on the host .”

However, most of the current knowledge comes rather from the large-scale scientific project Human Microbiome Project  (HMP), which took place in two phases from 2007 to 2016. Nowadays, it seems clear that the relationship between the human body and the gut microbiota is two-way. Symbiotic microorganisms adjust (lower) the pH of the intestine, which helps to reduce the frequency of pathogenic bacteria such as Salmonella or E. Coli .

Among the most frequently mentioned benefits  are the support of the integrity of the intestinal mucosa, the processing of undigested food residues or the support of immune functions thanks to the production of antimicrobial peptides or increased production of IgA.

• Are you interested in more about the effect of probiotics on the human body? Read our next article Probiotics and intestinal microflora: protectors and helpers in one .

In food supplements and regular foods, counted in the millions

You can buy probiotics as a dietary supplement in pharmacies or health food stores. The most common strains are Lactobacillus and  Bifidobacterium , in some cases it can also be specific yeast (e.g. Saccharomyces boulardii ).

However, probiotics are quite commonly found in foods that are not highly industrialized . Even  foods  such as fruits, vegetables and whole grains are sources of probiotic cultures. Among the richest sources, however, are fermented foods : fermented milk products, fermented vegetables or fermented soy products.

The dose of probiotics is normally calculated in the so-called KTJ, i.e. colonies forming a unit (English CFU). Rich sources of probiotics (dietary supplements, fermented milk products) contain at least hundreds of millions of them, i.e. a dose of 100 million colonies forming a unit in 1 capsule can be labeled as 1×10^8 KTJ.

However, there is currently no such thing as  a recommended daily dose of probiotics . A recent study showed that, depending on the type of diet, people consume an average of between one million and one billion units of CTU per day. For diarrhea associated with the use of antibiotics, it is recommended to take at least  5 billion KTJ per day .

 

8 Best Natural Sources of Probiotic Cultures

1. Kefir

Kefir is a traditional fermented milk drink made from kefir grains originating from the Caucasus and Tibet. Due to the fermentation process, it is slightly sparkling.

Of the probiotic cultures, kefir mainly contains lactic acid bacteria and yeast, which live in mutual symbiosis. The minimum amount of contained microorganisms is set at 1×10^7 KTJ in 1 g of the product.

2. Acidophilic milk

Acidophilus milk is characterized by the content of the probiotic culture Lactobacillus acidophilus in an amount of at least 1×10^6 KTJ/g . Other milk cultures such as Streptococcus thermophilus are often present.

Acidophilus milk has a sharp taste, so it is often mixed with sour cream to soften the taste . A slightly higher proportion of fat is also common, corresponding to about 3-4 g per 100 ml of product.

3. Yogurt

A mixture of two probiotic cultures is traditionally used to make yogurt: Lactobacillus bulgaricus and  Streptococcus thermophilus . These two strains live in synergy with each other, form the desired yogurt structure and  reduce the lactose content by approximately 20-30% .

In addition, some yogurt manufacturers use probiotic cultures of Lactobacillus acidophilus and  Bifidobacterium . These probiotics are among the best researched in terms of health benefits in human nutrition. The content of microorganisms is set at 1×10^7 KTJ in 1 g of product.

4. Kimchi

Kimchi is a collective name for various types of fermented vegetables, the consumption of which has more than a thousand-year tradition in Korea. This is also where it is most consumed to this day, with Korean adults eating an average of 130–150 g of kimchi per day .

Kimchi is fermented mainly by lactic acid bacteria , but at the same time it is processed by aerobic bacteria and yeast. It is also a very good source of prebiotic fiber and some vitamins, including vitamin B12.

5. Sauerkraut

Sauerkraut is a traditional fermented food that has been known since ancient Greece. It was also made famous by James Cook at the end of the 18th century as a “cure” against scurvy thanks to the vitamin C it contains .

Sauerkraut is a rich source of probiotic cultures, the dominant lactic acid bacteria is Leuconostoc mesenteroides . The use of salt in pickling is important because in its absence the growth of other microorganisms would be preferred.

6. Pickles

According to some estimates, cucumbers were already pickled about 5 thousand years ago . As with other types of fermented vegetables, the sour taste comes from the presence of probiotic microorganisms that produce organic acids.

Similar to sauerkraut, pickled cucumbers are also left to ferment in a slightly salty brine, which affects the composition of the microbial cultures. After about 15 days of fermentation, it is reported that the amount of microorganisms present can be up to 1×10^8 KTJ in 1 g of food .

7. Miso soup

Miso soup is one of  the most classic dishes of Japanese cuisine , where it is commonly eaten as part of breakfast. There are said to be more than 1,500 miso soup makers across Japan today.

Miso soup is made from soybeans, rice, salt and starter culture . In addition to probiotic cultures, Miso soup is rich in protein and contains a variety of antioxidants.

8. Actimel

Actimel is a commercial milk product particularly rich in probiotic cultures. One package contains 20 billion Lactobacillus casei probiotic cultures , which is many times more than the normal content of probiotics in fermented milk products.

Thanks to the high content of probiotic cultures, Actimel can be used during and after taking antibiotics to support the recovery of the intestinal microbiota .

When does it make sense to reach for probiotics in the form of food supplements?

In some situations , probiotics can be useful in the form of dietary supplements , which contain certain advantages compared to regular foods.

1. You know exactly which probiotics you are taking and in what quantity . It is also common to combine several different strains together together with prebiotics that facilitate the survival of microorganisms.
2. The amount of KTJ is often significantly higher than in ordinary foods .

Examples of these situations include:

• Taking probiotics during and after taking antibiotics . More than 5 billion CTU per day is recommended to reduce the negative effects of antibiotics on the digestive tract.
• When traveling to exotic countries . In particular, the yeast Saccharomyces boulardii together with the combination of Lactobacillus acidophilus and  Bifidobacterium bifidum seem to be an effective combination.

What to take from it?

Probiotics are live microorganisms that, when administered in adequate amounts, provide health benefits to the host. We can get them from dietary supplements or from regular foods , with the richest sources being fermented milk products and fermented vegetables. A diet rich in fermented milk products is up to 100 times richer in probiotic cultures compared to a diet in which fermented dairy products do not occur.

Include probiotics in the form of dietary supplements when taking antibiotics or when traveling to exotic countries . The advantages of these preparations include accurate knowledge of the microorganisms present and their number.