The Role Of Fermented Foods In Human Health

fermented foods human health

Fermented foods have played a very important role in human health. Fermentation predates modern human history. Not only is fermentation good for the preservation of foodstuffs, but is also good for the commensal bacteria strains found in fermented foods.

Modern Refrigeration

Modern Refrigeration has only been around for 100 years. 1854 was the beginning of modern refrigeration, 1918 was the beginning of the first domestic refrigerator, but mass production did not start until after World War II in the 1940’s.

Ice production for use in home ‘ice boxes’ began somewhere around 1830 but was not widely available. Although many living in colder climates were able to freeze food stuffs in the winter months, the majority of people living in warmer climates had to find other methods of food preservation.

Early refrigeration
1919 Advertisement

Prior To Modern Refrigeration

Prior to modern refrigeration, many methods have been used for preserving foods. Drying, boiling, canning, sugaring, pickling, adding lye, and burying. For the purpose of this article, I want to stick to fermentation as it has the longest verifiable history.

Fermentation History

The earliest archaeological evidence of fermentation is 13,000-year-old residues of a beer found in Haifa Israel. The neolithic Chinese began fermenting wines as early as 7000 BCE.

Beer and Wine are not the only things that humans ferment. Everything from sauerkraut and potatoes, to soy and hot sauce. Yogurt, pepperoni, fish sauce, shrimp paste, honey, vinegar, chocolate, sourdough bread, grain whiskey, millet porridge, kefir, tempeh, olives, and cheese are some of the many foods that utilize the fermentation process.

Why It Is Important

Since modern refrigeration has only been around for a blink of time in human history, and fermentation has a long history in food preservation, you can imagine that the commensal (or friendly) bacteria strains in fermented foods are important to our health.

While researching for my article on Colorectal Cancer, I came across a fascinating paper ‘Role of Lactobacillus reuteri in Human Health and Diseases’ (See: )

Lactobacillus reuteri (L.reuteri) is the most abundant bacteria strain found in many fermented foods. L.reuteri is known to be antimicrobial, and is active against common food-borne illnesses like salmonella and E.coli. Naturally produced antimicrobials can inhibit the growth of other bacteria as well.

I also found another recent paper that states that “Bacteria in fermented food signal the human immune system, explaining health benefits. Ability to detect bacteria may have enabled human ancestors to eat not-so-fresh food” I would encourage you to read the paper:

There is also evidence that Lactobacillus reuteri CRL1098 Produces Cobalamin (or vitamin B12). (See: At least 4 L. reuteri strains have been found to produce B12! (Tempeh can contain large amounts of B12 – See: Enhanced vitamin B12 production in an innovative lupin tempeh is due to synergic effects of Rhizopus and Propionibacterium in cofermentation. ).

An additional side note, Vitamin K2 is somewhat difficult for plant-based eaters to convert from K1 (See: The contribution of vitamin K2 (menaquinones) produced by the intestinal microflora to human nutritional requirements for vitamin K. ), however, some fermented foods, but especially tempeh is an excellent source of K2. (See: Determination of vitamin K composition of fermented food. ).

Interestingly, all of the ‘Blue Zone’ communities (areas with longevity and little chronic disease) around the world eat some type if fermented food. Check out my articles ‘Top 12 Longevity Foods‘ or ‘Lessons From Centenarians‘.

Top Longevity Foods

The Role Of L.reuteri In Human Health

L. reuteri is able to inhibit the colonization of pathogenic (harmful) microbes and remodel the microbiota composition, in essence balancing out our gut microbiome.

Some strains can reduce the production of pro-inflammatory compounds, and help regulate immune system function. The decrease in the abundance of L. reuteri in humans has been documented in the past decades, and correlated with an increase in the incidences of inflammatory diseases.

Some Lactobacillus have been used in the treatment of bacterial vaginosis, food hypersensitivities, and even in the prevention of dental caries. (See my article on ‘Dental Health and Diet – The Oral Microbiome‘). As mentioned above, L.reuteri is known to be antimicrobial, and also has been shown to be effective against a variety of GI bacterial infections.

L. reuteri has been shown to be an adherence mediator (helper) to Mucus-binding proteins in our intestines. It creates a biofilm that assists these proteins. In other words, it helps create a strong intestinal barrier so that pathogens cannot enter our bodies through our intestinal tract. It helps inhibit intestinal permeability (sometimes called ‘leaky gut’).

There are a host of other health benefits that have been documented using various strains of L.reuteri. Most of the testing that has been done is for the purpose of selling probiotic supplements and much of it done in mouse models. None-the-less, the documentation is there and if you are interested in learning more, I would encourage you to read the paper even though it is fairly technical.

My Theory

I believe that humans have ‘evolved’ with L.Reuteri (among other important commensal bacteria) and it is extremely important to our health. With modern refrigeration and food preservation, widespread antibiotic use, improved hygiene, and high fat diets – we have systematically decreased the abundance of L.reuteri in the human population.

What To Do

I do not personally recommend probiotic supplements. The supplement industry is highly unregulated and there have been numerous incidents of illness and even death documented from taking various supplements. The ONLY time I would suggest taking probiotic supplements is after antibiotic use, and it is best to consult your physician about the probiotics they recommend. (See my article: ‘Rebuilding Your Gut Microbiome After Antibiotics‘ )

The easy way to get more L.reuteri in your diet is by fermenting your own foods. You can purchase some commercially available fermented foods, but often the probiotic bacteria is lost/killed in the process of heat sterilization and sealing (like sauerkraut in a jar). Fermentation is simple and cheap. I have fermented sauerkraut, carrots, green tomatoes, and kimchi, and I eat plenty of tempeh and miso.

I would recommend purchasing fermentation lids like this one:

Lactobacillus reuteri  sauerkraut

Glass fermentation weights are also helpful and can be found on Amazon:

I will add some fermentation recipes soon, so please subscribe for occasional updates.

As always, if you have any questions about my content, please feel free to reach out to me directly ctiexec @ gmail dot com.