Background: Fermented foods have been used historically in many cultures to improve health and preserve foods. While losing popularity with modern processing and additive preservatives, 90% of fermented foods are still produced in the home. Fermented foods are associated with longevity and cultures such as the Japanese Okinowans, who eat foods such as natto, miso, tofu, shoyu, fermented vegetables, cholesterol-free, low-fat, and high bioactive-compounded foods in addition to active physical activity, sound environment, happiness and other several factors Research is focusing on improving our understanding of how and why naturally fermented foods provide health benefits.
Why eat fermented foods?
- They contain good bacteria which may improve digestion, boost, immunity, and help us maintain a healthy weight.
- Rich in probiotic bacteria.
- Increase the health of your gut microbiome, digestive system.
- Have anti-inflammatory properties.
- Produce enzymes to break down nutrients into more digestible and absorbable components.
- May decrease allergenic effects and promote tolerance to foods
- Promote bone health and may reduce osteoporosis- Vitamin K2 present in natto, as well as minerals such magnesium, calcium, phosphorus, potassium, and also protein present in yogurt may function together to promote formation of healthy bones.
- Lactic acid bacteria present in fermented foods may decrease number of incidence, duration and severity of some gastrointestinal disorders.
- A growing body of evidence supports fermented foods as demonstrating neuroprotective effects along with improvement in brain and cognitive function.
- Other specific health benefits include anti-oxidant, anti-microbial, anti-fungal, anti-inflammatory, anti-hypertensive, anti-diabetic, anti-cancer, and anti-atherosclerotic, which may lower risk of heart disease, diabetes, and cancer, etc. Kimchi, for example, is a fermented cabbage recipe that is known to be high in the probiotic properties of Lactobacillus plantarum, which can prevent growth of Helicobacter pylori. A variety of other bacterial species in fermented foods impede the growth of unwanted bacteria.
How does fermentation work?
- Through a process called lacto-fermentation, which is referring to lactic acid (and not dairy or lactose)
- Fruits and veggies typically have lactobacillus on their surface, which is are beneficial bacteria
- Bacteria produce active peptides such as conjugated lineoleic acids (CLA) which can lower blood pressure, have pre-biotic properties, have anti-microbial or anti-carcinogenic properties, etc.
- When put in an oxygen-free environment, the lactobacillus turns into lactic acid, which prevents the growth of harmful bacteria, preserves the produce, and gives the fermented foods a tangy flavor.
- The number of organisms in fermented foods can vary widely depending on how they were made, processed, and stored.
What does fermentation do?
- Promotes growth of good bacteria during the process
- Boost nutritional value of some foods, for example, B vitamins
- Breaks down the natural sugar in the food being fermented to make it easier to digest the food and absorb the nutrients
- The microorganisms created compounds such as lactic acid or alcohol, which helps preserves the food.
- Eliminates compounds called anti-nutrients which are natural or synthetic compounds which can interfere with absorption of nutrients.
- While lactic acid bacterial species are widely present in fermented foods, many other bacillus species and yeasts may be present depending on the food and starters used.
What kinds of foods are fermented?
- Dairy-yogurt, kefir, cheese
- Water-based-water kefir, kombucha
- Vegetables-cabbage (sauerkraut or kimchi), carrots, beets, pickling cucumbers, cauliflower, broccoli, radishes, green beans
- Fruit-apples (apple cider vinegar)
How do I get started on fermented foods?
- Work your way up to eating (a tablespoon or so) or drinking daily (1/4 cup), then graduate to with every meal if you can.
- When placed in an oxygen-free environment, Lactobacillus turns sugars into lactic acid. In turn, this lactic acid prevents the growth of harmful bacteria, acting as a preservative for the produce, and giving fermented foods their tangy flavor.
- Buy or make your own. You can make your own brine or purchase commercial starters depending on the bacteria you want to promote in the fermentation process. See my utube on making fermented vegetables at https://youtu.be/STtYTVXr6ac.
Are there health risks to fermented foods?
- Some individuals with impaired diamine oxidase activity due to being on Monoamine oxidase inhibitors (MAO’s), or with genetic predisposition may be sensitive to histamines which can be present when using some fermented starters.
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