Fermented food: An Ayurvedic perspective

In recent years, fermented foods have gathered a lot of attention as the holy grail for good gut health. From sauerkraut, to kombucha and kefir to sourdough bread, it’s everywhere.

So what is fermented food?

Fermentation is a natural chemical process that occurs when microorganisms (bacteria or yeast) convert energy from carbohydrates (sugars) in an environment without oxygen. The outcome is alcohol, lactic acid and gases which gives the food its characteristic tangy flavour.

Humans have been fermenting foods for thousands of years. It helps to preserve the food which was very helpful in a time without fridges and packaging to prolong their shelf-life.

Benefits of fermented foods

Fermented foods are partially digested (by bacteria or yeast) and this makes them more bioactive and bioavailable, easier for us to digest. They also contain some live microorganisms which are similar strains to those which support our gut health (probiotics) and reduce inflammation.

Fermented foods increase the bioavailability of polyphenols (antioxidants) from food. Antioxidants work to scavenge pathogens, keeping our gut safe and healthy.

Some fermented foods have shown to contain high levels of short-chain fatty acids (SCFA). SCFA are the product of the natural breakdown of sugars by our own microbes in the gut. They are used as an energy source for colon cells and are used to build the gut wall lining. SCFA also stimulate the production of mucous from our body’s own cells to coat the gut lining. This mucous has two functions – it protects our gut wall and also feeds our own gut cells. Again, this is great because it helps to strengthen our gut wall, making sure no bacteria leaks into our bloodstream so that we become unwell.

A point to consider here is that while some fermented foods such as kimchi, kefir or sourdough bread are made using a few fresh ingredients, others such as the typical loaf of packaged Hovis bread will contain a long list of artificial ingredients (emulsifiers, preservatives, artificial sweeteners). These additional ingredients can play havoc with your gut health. So, choose carefully.

The Ayurvedic view

As with everything in nature, Ayurveda categorises food according to their qualities. Qualities in terms of the taste they produce, the elements they contain and so the action they have within the body. Fermented foods have a sharp and sour taste. They are fiery in nature and so will stoke the digestive fire within us. This is great for someone who has sluggish digestion such as someone with a Vata or Kapha make-up. However, give a Pitta person too much fermented food on a hot Summer’s day and you might see a reaction e.g. heartburn, rashes, acid reflux, loose stool or heavy periods in women.

You’ll notice that Ayurvedic diet and nutrition plans that include bread will state that the bread should be without yeast or unleavened. Ayurveda traditionally used fermented wines for medicinal purposes and it is here that we can see that it’s considered to be something to be taken in small quantities, not in excess.

Conclusion

The takeaway message is that fermented foods no doubt have numerous benefits for our gut health. However, as with all foods, it’s important to understand that not all foods will suit all people – while fermented foods can be a useful addition for some, it will irritate the constitution of others.

Universal tips:

• Eat fresh

• Eat seasonally

• Eat according to your constitution and according to your current state of health

References

Hansson, G.C. (2012) Role of mucus layers in gut infection and inflammation. Current Opinion in Microbiology, 15(1)

Lad, V. (2012) Textbook of Ayurveda: General principles of management and treatment. The Ayurvedic Press: Albuquerque

Lee, H.C., Jenner, A.M., Low, C.S. and Lee, Y.K. (2006) Effect of tea phenolics and their aromatic fecal bacterial metabolites on intestinal microbiota. Research in Microbiology, 157(9)

Leeuwendaal, N.K., Stanton, C., O’Toole, P.W. and Beresford, T.P. (2022) Fermented foods, health and the gut microbiome. Nutrients, 14(7)

Schroeder, B.O. (2019) Fight them or feed them: how the intestinal mucus layer manages the gut microbiota. Gastroenterology Report, 7(1)