Long consumed by humans, fermented food has been a dietary staple for thousands of years.
But why has fermented food always enjoyed such popularity? Was it just a way to preserve food before refrigeration was available, or is there more to it than that?
This article will take a look at the health benefits of eating fermented food and whether or not you should be eating it.
What Are Fermented Foods?
One of the most traditional ways of fermenting food is to use the lacto-fermentation process.
In very simple terms; the process starts by soaking vegetables in either water or salted water. The natural bacteria starts eating the vegetables; lactic acid levels rise, and the harmful bacteria die while the good bacteria survive.
This process has many benefits; it helps improve both the nutrient profile and digestibility of the food.
In addition to this, fermentation creates good bacteria and enzymes that benefit our health, preserve the food, and create new flavors.
All our ancestors had these foods in their diet; Europeans consumed cheese, sauerkraut, wine, and yogurt.
In Asia; kimchi, natto, and various fermented fish recipes remain popular after centuries of consumption.
The Lost Tradition of Fermented Food (in the West)
Fermentation was necessary to preserve their fresh produce. Vegetables would quickly go bad in summer, and die in winter.
Of course, Korea and Japan are two of the biggest economies in the world. They have access to modern consumer electronics. Every house has a refrigerator and they no longer need cultured vegetables.
But they still ferment their food, and they are still enjoying the health benefits of eating fermented food every single day.
In Western countries, it is very different. We tend to use canning processes and chemical preservatives to keep our food fresh.
Our way of preserving food puts convenience first, but when it comes to health, it doesn’t hold a candle to traditional methods. Canned foods contain environmental, bacterial and heavy metal contaminants, as well as Bisphenol A (BPA) (1, 2, 3, 4)
Several studies over recent years have also linked chemical preservatives to allergic reactions, asthma, intestinal damage, and many other health problems (7).
Unfortunately, though, the majority of consumers have a desire to continue buying packaged foodstuffs from supermarkets. Above all, they value convenience despite being aware of the dangers (8).
As a society, we have indeed lost the art of fermentation. But is that a problem? Let’s take a look at some of the health benefits of eating fermented food and see.
5 Health Benefits of Eating Fermented Food
We are only recently re-discovering the importance of gut health and probiotics. But here is a list showing five health benefits of fermented foods that we do know of.
1Fermented Foods Improve Gut Health and Microbiota Balance
Our gut is an integral yet overlooked predictor of overall health.
I’m sure you know that what you eat plays an important role in your health, but in addition to that; you can only get nutrients from foods that you can actually digest.
If you’re not digesting food properly, then you can be eating the healthiest diet in the world and it won’t matter. Optimal functioning of the digestive system is important for absorbing the nutrients properly (9, 10, 11, 12).
This is where fermented foods are beneficial.
When you consume fermented foods, beneficial probiotics (otherwise known as ‘good bacteria’) enter your digestive system.
Bacteria such as lactobacillus and bifidobacterium both produce lactic acid and support the optimal breakdown of food during digestion.
The good bacteria from fermented foods helps us digest food, destroy bad bacteria capable of causing disease, and aid in the manufacture of vitamins (13).
Additionally, the ratio between good and bad bacteria in our gut play a role in the development (or prevention) of many health issues.
The research in this area is very raw but it’s a fast emerging field. Recent studies link our gut health to cancer, heart disease, and dementia risk, as well as several other chronic conditions (14, 15, 16).
2Fermented Foods and Diabetes Risk
Fermented foods relate to diabetes in several ways.
Fermented foods contain lacto-fermented carbohydrate, making them pre-digested. This makes them much less taxing to the pancreas and overall digestive system.
Additionally, fermented foods contribute to a healthy gut microbiota. There is some interesting research in regard to gut health and type 2 diabetes.
A 2012 study analyzed gut microbial DNA from 345 individuals and found that each participant with type 2 diabetes had an imbalanced gut flora, a decrease in beneficial bacteria and an increase in ‘opportunistic pathogens’ (17).
A study back in 2010 investigated this by analyzing 36 adult males, 18 of whom had type 2 diabetes. There was a richer variety of beneficial bacteria in the non-diabetics across the group (18).
Further research suggests that intestinal microbiota plays a large role in the prevention of metabolic dysfunction in humans.
We can see the same negative changes in bacterial diversity in both obesity and diabetes. Evidence shows that feeding a high-sugar western style diet for 8 weeks creates an altered gut microbiota (19, 20).
The gut microbiota may also play an important role in preventing diabetes-related ‘complications’ such as foot ulcers, atherosclerosis, and diabetic retinopathy.
This is suspected to be through the further development of T2D as a result of an imbalanced microbiota’s contribution to inflammatory components (21).
It is worth remembering that refined carbohydrates and simple sugars have strong links to both T2D and an imbalanced gut flora.
3Fermented Foods Increase Resistance to Harmful Bacteria
Fermented food consumption leads to greater antimicrobial activity in the gut.
This is through the production of beneficial microbes that defend against pathogens and bad bacteria.
Some of these microbes are even capable of removing procarcinogens and alleviating allergy symptoms (23).
As well as this individual impact microbes make, they also stimulate the immune system.
4Fermented Foods and Mental Health
You might not imagine the link between fermented food and your mental health, but recent studies show a strong connection.
Lack of dietary fermented foods has links to:
- Increased levels of anxiety
- Difficulty processing emotions
- Social withdrawal
A healthy gut microbiome is essential for optimal wellbeing and your mental health is no exception.
There are a wealth of studies in this area and some recent research indicates that:
- Higher frequency of fermented food consumption is associated with less anxiety (27).
- The probiotic bifidobacterium decreases anxiety-like behavior in mice (28).
- Lactobacillus bacteria appears to have an effect on the central nervous system (CNS) and reduces stress hormones, lessening the effect of anxiety and depression (29).
- In several controlled studies, groups supplementing probiotics had improvements in anxiety and depression versus placebo. Additionally, stress hormones were lower (30).
- In a randomized, double-blind controlled study, participants took lactobacillus or a placebo for two months. The results showed that in those taking the lactobacillus, they had a much higher level of the bacteria in their gut. They also had a significant decrease in anxiety compared to the placebo (31).
- A study last year took fecal samples from 46 patients with major depressive disorder (MDD) and 29 from healthy individuals. The samples from those with MDD had a higher amount of harmful bacteria and a lower amount of beneficial bacteria (32).
5Fermented Foods and Obesity
A gut microbiome with an imbalance of good and bad bacteria has strong associations with obesity.
Extensive research exists in this area and much of it shows the beneficial impacts of fermented food.
The staple food of Korea, Kimchi, comes in two varieties; fresh and fermented.
Both are popular, but in controlled studies comparing the two, fermented kimchi showed a much more significant effect on weight reduction and decreasing body fat percentage (33).
A 2015 study investigated the influence of the gut microbiota on obesity, metabolic syndrome, and gastrointestinal disease.
The diagram below shows how the authors of this study differentiated between altered microbiome states and health impacts.
The study presented findings explaining how colonies of beneficial gut bacteria are protective against obesity.
Additionally, they found evidence linking early childhood exposure to antibiotics with obesity. It’s common knowledge that antibiotics adversely impact the population of our microbiome (34).
Another study that investigated the differences between ‘obese’ and ‘lean’ microbiomes found that there were clear differences between the two.
The ‘obese microbiome’ had an increased capacity to harvest energy from food (35).
Best Fermented Foods
Now that you know the benefits of fermented foods, perhaps you’re wondering how to incorporate them into your diet?
Here is a list of some fermented foods that may help you.
Maybe the world was blind to kimchi 5 years or so ago. But these days, almost everyone has heard of the Korean fermented cabbage and rightly so – it tastes great and improves your health.
What is Kimchi?
Kimchi is a fermented vegetable. Cabbage is seasoned with fish sauce, red pepper flakes, garlic, ginger and salt, and then left to ferment.
Kimchi Health Benefits
Kimchi is regarded as having anti-obesity, anticancer, probiotic and antioxidative properties.
The effects of kimchi can be attributed to the wide range of beneficial compounds created by the fermentation of garlic, ginger, fish, and cabbage (36).
This traditional German food is known and loved throughout Europe. Like Kimchi, the major ingredient of sauerkraut is cabbage. But that’s where the similarities end.
What is Sauerkraut?
Making sauerkraut is relatively easy. The cabbage is simply layered, covered in salt, and then left to ferment.
Sauerkraut Health Benefits
Sauerkraut is rich in vitamins A, C, K and B-vitamins, as well as a wide range of essential minerals (37).
Regular consumption of sauerkraut has links to many health benefits; research is ongoing into the impact sauerkraut has on reduced incidence of cancer and allergic reactions.
Many researchers believe fermented cabbage is healthier than raw or cooked cabbage, and it contains an anti-cancer compound, but more research is needed (38).
Who doesn’t love cheese? If you’ve tried raw cheese you’ll appreciate the fuller flavor and probiotic content.
What is Raw Cheese?
Raw cheese is simply cheese that hasn’t been pasteurized. During the pasteurization process, dairy is exposed to high heat which kills beneficial bacterial strains and enzymes contained in the milk/cheese.
Raw Cheese Health Benefits
Cheese contains a range of beneficial bacterias that high temperature destroys when heated to 47/48°C, hence raw cheese retains this benefit while pasteurized cheese does not (39).
Yogurt is one of those rare foods that almost everyone agrees about. It has numerous documented health benefits.
What is Yogurt?
Yogurt is a dairy food prepared from fermented milk. Beneficial bacterial strains added to the milk start the fermentation process. Yogurt comes in several varieties; ideally, choose plain yogurt and stay away from low-fat versions.
Yogurt Health Benefits
Yogurt is particularly high in calcium and phosphorus and contains beneficial probiotics.
Based on a survey of 41,436 men, yogurt was consistently and inversely associated with type 2 diabetes risk (40).
Additionally, in a prospective study of 45,214 volunteers, yogurt consumption showed a significant inverse association with colorectal cancer (41).
Some people dismiss the importance of fermented foods, viewing them as an unnecessary addition to our diet.
However, the reliance on fermented foods by our ancestors around the world hints at their historical value. Recent science suggests the same.
Our understanding of the gut microbiome is only in its infancy and new information is rapidly emerging.
But based on the current science; I would say fermented foods should play an important role in any diet.
A balanced gut flora has strong links to immunity against a wide range of health conditions and eating small amounts of cultured vegetables each day can introduce millions of beneficial bacteria into our gut.
It’s not hard to do; it has big health benefits, and fermented food tastes great.
Do you eat fermented foods? Which ones do you like best?