When most of us think of fermentation, we think of wine and beer, but fermented foods are increasingly popular and have been found to have a few surprising potential health benefits.
The History of Fermentation
Fermentation has long been practiced as a culinary technique to preserve fruits and vegetables so as to keep the pantry full year-round, even when refrigerators, freezers, and other modern appliances didn’t exist. In many cultures, fermented foods such as kimchi are considered a staple part of the diet, allowing people to eat some foods out of season so as to carry them through the winter until next harvest.
Some estimates, based on measuring the chemical content of ancient Neolithic vessels, suggest that people began to intentionally ferment fruit, rice and honey around 10,000 years ago. Fermentation then became popular as a way of enhancing or altering the flavour and lifespan of foods such as cereals, dairy, vegetables, fish, seafood and meats.
The Fermentation Process
In addition to keeping us fed year-round and providing us with such delicious things as miso and kimchi, fermentation has been shown more recently to have potential benefits for digestion, and even for emotional and cognitive health (Ano et al., 2015; Andoh, 2016).
The possible effects of fermented foods are due in part to the changes that occur in the foods during fermentation, including enriching the food with, for example, lactoferrin and bioactive peptides, and even creating new phytochemicals such as unique flavonoids (Selhub et al., 2014).
Fermented Foods and Gut Bacteria
Fermented foods also modulate our microbiome, i.e. the bacteria that live in our bodies and that influence a number of parameters of health. The make-up of bacteria in our gut can affect how we digest food, and may modulate the production of pro-inflammatory substances (Selhub et al., 2014).
Bacteria may even play a role in the synthesis of neurotransmitters that can influence appetite and mood. Some bacteria are directly involved in the creation of neurotransmitters like gamma amino-butyric acid (GABA), while others have an indirect effect on neurotransmitter synthesis (Mangiola et al., 2016).
Dietary Benefits of Fermented Foods
Some researchers have suggested the benefits seen with some ways of eating, such as the Mediterranean diet or traditional Japanese diet, may be due in part to the inclusion of fermented foods in these diets. Indeed, studies have found that traditional Japanese dietary practices (where the diet includes vegetables, mushrooms, fruit and fermented products such as tamari and miso) have been associated with lower rates of depressive symptoms (Nanri et al., 2010; Suzuki et al., 2013).
Additional research has found that fermented foods may support the body in regulating blood sugar levels while providing antioxidant activity to stave off oxidative damage (Aruoma et al., 2014). They appear to help maintain the lining of the gut, supporting healthy immune and inflammatory responses and encouraging the absorption of vitamins, minerals and other essential nutrients (Choi et al., 2014; Selhub et al., 2014; Bering et al., 2006).
By offering possible support for gut health, energy metabolism, and normal inflammatory responses, fermented foods certainly seem to have earned a place at the table. What’s more, a jar of homegrown, home fermented kimchi, gherkins, asparagus or other delights, make for an attractive and unusual gift!
Ano, Y., Ozawa, M., Kutsukake, T., Sugiyama, S., Uchida, K., Yoshida, A., Nakayama, H. (2015). Preventive effects of a fermented dairy product against Alzheimer’s disease and identification of a novel oleamide with enhanced microglial phagocytosis and anti-inflammatory activity. PLoS One, Mar 11;10(3):e0118512.
Andoh, A. (2016). Physiological Role of Gut Microbiota for Maintaining Human Health. Digestion, Feb 9;93(3):176-181.
Aruoma, O.I., Somanah, J., Bourdon, E., Rondeau, P., Bahorun, T. (2014). Diabetes as a risk factor to cancer: functional role of fermented papaya preparation as phytonutraceutical adjunct in the treatment of diabetes and cancer. Mutat Res, Oct;768:60-8.
Bering, S., Suchdev, S., Sjøltov, L., Berggren, A., Tetens, I., Bukhave, K. (2006). A lactic acid-fermented oat gruel increases non-haem iron absorption from a phytate-rich meal in healthy women of childbearing age. The British Journal of Nutrition 96(1):80-85.
Choi, J.Y., Paik, D.J., Kwon, D.Y., Park, Y. (2014). Dietary supplementation with rice bran fermented with Lentinus edodes increases interferon-γ activity without causing adverse effects: a randomized, double-blind, placebo-controlled, parallel-group study. Nutr J, Apr 22;13:35.
Mangiola, F., Ianiro, G., Franceschi, F., Fagiuoli, S., Gasbarrini, G., Gasbarrini, A. (2016). Gut microbiota in autism and mood disorders. World Journal of Gastroenterology, 22(1), 361–368.
Nanri, A., Kimura, Y., Matsushita, Y., Ohta, M., Sato, M., Mishima, N., Sasaki, S., Mizoue, T. (2010). Dietary patterns and depressive symptoms among Japanese men and women. Eur J Clin Nutr, 64:832–839.