Noyes News and Events

July 15, 2017

Sauerkraut, Kombucha, and Kimchi, oh my!

Growing up in a Slavic household, I was no stranger to sauerkraut.  The tangy, fermented cabbage dish was a dinnertime staple especially through the winter months.  About ten years ago, our family tried another fermented cabbage dish, kimchi.  A young man from South Korea introduced us to the spicy, slightly fishy side dish. Fermented foods like sauerkraut, kimchi, kombucha (a fizzy fermented tea), yogurt, and sourdough bread have gained a lot of attention over the past decade.  However, the popularity of these foodstuffs goes beyond taste and grocery story marketing.  They are getting a lot of press in the scientific world as researchers discover that the good for you bacteria present in fermented foods may help with cardiovascular disease, type 2 diabetes, irritable bowel syndrome, and possibly mental health.

Fermented foods have been in the human diet for thousands of years.  Wine, beer, yogurt, pickled vegetables, and sausages like salami (made the old-fashioned way) have been household staples around the globe for centuries.  Fermentation is the conversion of a carbohydrate such as sugar into an acid or alcohol.   While the process can occur naturally without any intervention, most fermented foods are produced by adding yeast or bacteria to change sugar to alcohol or lactic acid.  Beer is made by taking a grain such as barley, germinating and drying it, and then pulping it into a mash.  The mash is mixed with hot water and some fermentation begins.  Yeast is then added.  The yeast “eats” the mash sugar and converts it to carbon dioxide and alcohol. Wine is made in a similar fashion.   Yogurt, on the other hand, is made by adding a number of special bacteria, such as L. acidophilus and L. bulgaricus to milk.  The bacteria convert the dairy sugar to lactic acid, eventually creating yogurt.

The fermentation process increases shelf life, creates new tastes and textures, and produces beneficial compounds.  During dairy fermentation, many helpful compounds are produced or increased such as vitamin B-12, folic acid, and biotin.  The mineral concentration of calcium, magnesium, potassium, phosphorus, and zinc are nearly 50% higher in yogurt than in milk.  Yogurt is also an excellent source of “good for you” bacteria or probiotics.  A probiotic is any live microorganism that when consumed in adequate amounts offers some sort of health benefit.  Various clinical studies indicate that the ingestion of yogurt and other fermented dairy products (kefir, skyr, cheese) is significantly associated with decreased disease.  The strongest evidence is the use of the bacteria found in yogurt for the treatment of diarrhea (especially caused by antibiotics.)  Further studies in the Netherlands, Sweden, and Denmark, found decreases in bladder cancer, cardiovascular disease, and periondontitis among those with higher fermented dairy intake.  A 2011 study published in the New England Journal of Medicine revealed strong associations between the consumption of fermented dairy foods and weight maintenance.  Extensive studies also show a reduction in the risk of cardiovascular disease, type 2 diabetes, and overall mortality for frequent yogurt eaters.
Similarly, evidence is accumulating for the benefits of kimchi.  A 2013 study found that fermented kimchi has anti-diabetic and anti-obesity benefits.  Peptides and other compounds created in the fermentation process are being investigated for their possible beneficial effects on hypertension, clots, the immune system and more.  One theory called the hygiene or diversity hypothesis proposes that bacterial exposure is essential for the normal development of the immune system and brain function.  A 2017 report in the Current Opinion in Biotechnology, therefore, suggests, “Consumption of fermented foods may provide an indirect means of counteracting the hygienic, sanitized Western diet and lifestyle.”  Moreover, while we are a long way off from prescribing fermented foods for depression and other mental health issues, a 2014 analysis in the Journal of Physiological Anthropology indicates that there is ample justification for further research into gut-brain health.  Authors of the study submit that fermented foods have the potential to influence brain health due to probiotics that magnify antioxidant and anti-inflammatory activity.   

Our ancestors perfected the production of various fermented fare over the centuries and made it part of their daily dietary life.  Due to the increase in processed foods, the diversity and amount of fermented foods decreased over the last century.  Those numbers are increasing once again as science confirms the health benefits of humble foods like sauerkraut!

Here are some helpful hints as you consider adding fermented foods into your diet:

  • Speak with your doctor if you have a compromised immune system.  Fermented foods may not be recommended for certain conditions as they could be carcinogenic or contain high levels of sodium or sugar. 
  • Eat and drink fermented foods as part of a healthy diet that includes fresh fruit, vegetables, whole grains, and lean proteins.
  • Read ingredient and nutrition labels.  For example, to reap any benefit from yogurt, it must contain live cultures.  Eat plain, low-fat yogurt and add fresh or frozen fruit to sweeten.  Many commercially fermented foods have added sugars, salt, and are pasteurized.  As a result, they have little to no nutritional or probiotic benefits.  Look for non-pasteurized options with live cultures. 
  • Examples of fermented foods include: sauerkraut, kimchi, kombucha, tempeh, yogurt, kefir, skyr, pickles, olives, natto (forms the base of miso used in Japanese cooking), and red wine.

Lorraine Wichtowski is a community health educator at UR Medicine Noyes Health in Dansville.  If you have questions or suggestions for future articles, she can be reached at lwichtowski@noyeshealth.org or 585-335-4327.