All too often I come across articles that exaggerate the potential health benefits of specific foods. For example, if you do a google search on the impact of garlic on human health, you could quickly be led to believe that this bulbous plant can cure everything from cancer to heart disease. As you know if you’ve been reading this blog for some time, I clearly believe in the healing power of food. However, I think it’s much more important to focus on the overall quality of our diet and the impact food has on gene expression, the inflammatory milieu in the body, and the microbiome, rather than on eating massive amounts of one or two “superfoods”.
Most of the time, adding a single food to your diet isn’t going to have a strong, noticeable effect on your health. Fermented vegetables may be an exception, because a lot of people in the modern world have a dysfunctional gut microbiota that is in desperate need of some influx of beneficial bacteria.
Reconnecting with some old microbial friends
Few, if any, people in contemporary Western societies harbor what could be considered a truly healthy microbiota. At first, you might find this to be an extreme statement. However, if you consider the fact that most of us have taken several courses of antibiotics, drink chlorinated water, eat processed foods, spend most of our time indoors, and otherwise live in an environment that is completely different from those our ancestors evolved in for millions of years, you probably realise that it’s not.
Since the lifestyle of an individual who live in an urban, modern environment is very different from that of a hunter-gatherer or a person living in an isolated, non-westernized part of the world, he’s not necessarily best of harboring a microbiome that is similar to theirs. However, studying the microbiome of traditional people and hunter-gatherers is important, as it gives us many hints as to what could be considered the “evolutionary norm” for our species.
As those who’ve been following this blog know, studies consistently show that hunter-gatherers and traditional people minimally affected by modern lifestyle habits harbor gut microbiotas that are characterized by much greater biodiversity when compared with a “Westernized microbiota”. Basically, there’s plenty of evidence to suggest that we’ve lost some microbial “old friends” that co-evolved with our ancestors for millions of years. Not only that, but many of us have altered our microbiome in such a way that we’ve ended up with a dysbiotic microbiota dominated by proinflammatory germs.
So, how can we restore our microbiota to a healthier state? As you know if you’ve read this blog for some time or kept up-to-date on what’s going on in the world of the microbiome, there are a lot of things that can help out, ranging from the small things such as eating more fiber and doing some gardening to the more aggressive treatment with a fecal microbiota transplantation. While there are no single magic bullets that can get you a healthy microbiota for life, there are certain things that can have a strong positive impact. One of these things is fermented vegetables.
To be sure, I’m not talking about the pasteurized “sauerkraut” you find in the aisle of your grocery store. Rather, I’m talking about raw, traditionally fermented vegetables. Fermented vegetables can easily be made at home. In some countries you can also find high-quality, fermented vegetables at farmer’s markets, health food stores, etc.
Fermented foods as part of ancestral diets
Here’s a quote from a recent paper by one of my favorite researchers, Dr. Alan C. Logan, that summarizes the role of fermented foods in ancestral diets.
… our Paleolithic ancestors had plenty of opportunity for the consumption of food products (for example, honey, fruits or berries, and their juices) that had been unknowingly subjected to natural microbial fermentation. Without knowledge of microbes, our ancestors recognized, over time, the palatability, preservative, analgesic, and mentally stimulating or sedating qualities of fermented foods and beverages. Thus, the stage was set for the purposeful application of fermentation to provide value in the areas of human nutrition, traditional medicine, and culture (ceremonies, and so on). It is difficult to say with certainty when intentional fermentation began in earnest; however, sophisticated measurements of the chemical content within ancient Neolithic vessels suggest intentional fermentation of fruit, rice, or honey beverages has been in common practice for close to 10,000 years. As agriculture expanded, so too did intentional fermentation techniques. Beyond the clear references to alcohol production, it is now obvious that household and artisanal fermentation of cereals, dairy, vegetables, fish, seafood and meats were a significant part of ancestral dietary practices. (1)
6 health benefits of eating fermented vegetables
1. Fermented vegetables improve your gut health
Fermented vegetables are a rich source of lactic acid bacteria. For example, DNA fingerprinting has shown that commercial sauerkraut fermentations contain lactic acid bacteria such as Leuconostoc mesenteroides, Lactobacillus plantarum, Pediococcus pentosaceus, Lactobacillus paraplantarum, and Lactobacillus brevis (2).
While a lot of people notice a strong improvement in gut health from consuming fermented vegetables, it’s important to note that sauerkraut, kimchi, and all of the other delicious lacto-fermented veggies out there don’t provide the wide spectrum of microorganisms that are needed for a well-functioning gut microbiota. In other words, eating some sauerkraut or kimchi isn’t going to be enough to treat severe gut dysbiosis. However, that doesn’t mean the bacteria found in fermented vegetables won’t have any effect.
The lactic acid bacteria in fermented vegetables help regulate intestinal barrier function, provide protection against infections and pathogenic biofilms, and may colonize the gut and/or contribute genetic material to residential gut bacteria through horizontal gene transfer (1, 3, 4). Homemade fermented vegetables may also provide other beneficial microbes besides the most commonly found species of lactic acid bacteria (5).
2. Fermented vegetables can improve your mood and mental health
The microbiome-gut-brain axis has received a lot of attention both in the scientific community and mainstream press lately – and for good reason. Over the last decade we’ve learned that the gut microbiota impacts our mood, behaviour, and thoughts, and to some people’s surprise, even our food preferences and appetite.
By now it’s well established that depression and several other mental health disorders are characterized by chronic, low-grade inflammation and oxidative stress (1, 6). Given the potent anti-inflammatory effects of beneficial gut bacteria, as well as their ability to produce compounds (e.g., neurotransmitters) that reach our brain, it shouldn’t come as a surprise that probiotics can help improve our mood and mental outlook.
In the same paper that was quoted above, the authors conclude:
“… the fermented foods so often included in traditional dietary practices have the potential to influence brain health by virtue of the microbial action that has been applied to the food or beverage, and by the ways in which the fermented food or beverage directly influences our own microbiota. This could manifest, behaviorally, via magnified antioxidant and anti-inflammatory activity, reduction of intestinal permeability and the detrimental effects of LPS, improved glycemic control, positive influence on nutritional status (and therefore neurotransmission and neuropeptide production), direct production of GABA, and other bioactive chemicals, as well as a direct role in gut-to-brain communication via a beneficial shift in the intestinal microbiota itself” (1).
3. Fermented vegetables positively impact immune function
Good health starts in the gut. This can easily be appreciated when we consider the fact that more than 70% of our immune system is located in and around the gastrointestinal tract, with gut-associated lymphoid tissue (GALT) being the prominent part of mucosal-associated lymphoid tissue (MALT) (1).
4. Fermented vegetables can help prevent and treat skin conditions like acne
Those who’ve followed the research on the microbiome know that gut dysbiosis and leaky gut play a role in the development of many skin disorders. For example, as I’ve previously discussed on the blog, I believe poor gut health is the main underlying cause of acne vulgaris. This belief is supported by recent research which connects leaky gut and gut dysbiosis with the development of acne and highlights the potential of prebiotics and probiotics in the treatment of this skin condition (8).
5. Fermented vegetables can help you lose weight
In my recent 4-part article for Paleo Magazine I discussed the relationship between gut bacteria and weight regulation. One of the main takeaways from that series is that gut dysbiosis and increased intestinal permeability (“leaky gut”) can set the stage for chronic low-grade inflammation, decreased leptin and insulin sensitivity, and weight gain.
Lactic acid bacteria have anti-obesity effects and may aid weight loss (9, 10). For example, studies have shown that fermented kimchi, a popular side dish originating in Korea, reduces body weight and improves metabolic parameters in overweight and obese patients (11, 12).
6. Fermented vegetables aid in the protection against chronic disease
Given the profound impact gut bacteria have on everything from our immune system to metabolism to brain function, it shouldn’t come as a surprise that nutrient-dense foods rich in beneficial bacteria can help enhance our protection against chronic disease.
For example, consumption of Kimchi has been associated with numerous health benefits, including, but not limited to, increased protection against cancer, obesity, and diabetes and reduction in cholesterol levels (13).
Our primal ancestors evolved in a microbe-rich, natural environment, ate food with plenty of clinging soil bacteria, and may even have consumed some raw animal intestines every now and then. In other words, adding some fermented vegetables to your diet isn’t going to give you the gut microbiota of a hunter-gatherer. However, of all the diet changes you can make to improve your microbiome, it is high on the list of the most effective ones. Also, since adding some high-quality fermented foods to the diet doesn’t take much work or effort, it’s really something everyone who are looking to improve their gut health should consider.
A lot of people reading this blog are probably already eating fermented vegetables such as kimchi and sauerkraut on a regular basis, but if you aren’t, adding them to your diet may quickly end up being one of the best things you’ve ever done for your health. To further enhance the health of your gut microbiota – and consequently your overall health, make sure you’re exposed to other sources of beneficial bacteria and eat plenty of prebiotic fiber.
Personally, when I first added high-quality fermented vegetables to my diet, I noticed a strong improvement in my gut health and overall well-being. I now eat fermented root vegetables and sauerkraut on a regular basis.
Are fermented vegetables a part of your diet? If yes, which ones to you eat, do you make them yourself at home, and do you feel they have a noticeable effect on your health?