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Cultured Food and its Role in the Immune System (Immunity part 1)

Posted on Wednesday 23 September 2020

By Diana Earnshaw

With autumn on the horizon, it is the right time to boost your immune system for the winter. Viruses thrive in the cooler conditions but there are many anti-viral foods at our disposal – so best we use them. AND – it is ORGANIC September so shopping for these foods at True Food is the right choice!

Our immune systems help us to keep us safe from illness. You can only be protected by giving your body the right building blocks, so food plays an enormous part in keeping the immune system in working order.  A number of vitamins (A, B6, B12, folate, C, D3 and E) and trace elements (zinc, copper, selenium, iron), have been shown to support the human immune system. However, there is also evidence that foods contain more than just these – they also contain antioxidants. Fermenting food improves our uptake of all these wonderful chemicals.

“The gut microbiota plays a role in educating and regulating the immune system. Gut dysbiosis  (this means that our microbes  are out of balance) is a feature of disease including many infectious diseases and has been described in COVID-19. Dietary approaches to achieve a healthy microbiota can also benefit the immune system.”
This extract is from an article in the British Medical Journal (BMJ).  So as you can see, our gut is extremely important! Some people take pro-biotic supplements, but generally speaking, pro-biotic foods contain more strains of beneficial microbes and they are more likely to resist the acid in the stomach. This means they will reach the intestines where they have their immune system- boosting effect.

With so many lovely vegetables available at the moment, why not have a go at fermenting some of them?

As we know, there are lots of benefits to making vegetables a part of our diet. They are full of nutrients – known and unknown! There are nutrients in vegetables that we know are present – but they don’t all have names yet. We call these “phyto-nutrients” and there are probably very many of them. Lycopene – found particularly in tomatoes - was one of these, but now has a name. Lycopene is a nutrient that is currently being studied. It is believed to be protective in two ways – possibly preventing prostate cancer and helping to prevent cardio-vascular disease.
These phyto-nutrients may well turn out to be healing to us and herbalists have known this forever! Many of our mainstream drugs have their origins in plants.

Vitamins and minerals abound in vegetables. If a mineral is in the soil – it will almost certainly be in the plant. This is a very good reason to eat organic food, because the soil will have been liberally supplied with natural fertilisers and therefore be rich in minerals.


The nutrients will vary in vegetables, depending in part upon whether they grow below or above ground. The leaves for example, will have lots of vitamin C, vitamin K1 and folate and there will be less in the roots, but they will often be richer in fibre. 

As well as nutrients, all plant foods contain “anti-nutrients” too. These are chemicals that can upset our digestion and absorption of nutrients. This is the plant’s defence mechanism to prevent predators eating them to extinction! This is not a problem as long as we prepare them correctly – as our ancestors did. We must cook them well, sprout them or ferment them. These methods destroy almost all the anti-nutrients, making them easier for us to digest and absorb.

It is worth noting, that all bought sauerkraut is not the same. If it is sold from a fridge, it will be live and pro-biotic. If it is on a shelf, it is a condiment and has been pasteurised and is therefore not pro-biotic.

Fermenting food is an age-old method of preserving. Before we had refrigeration, this way was the only way to keep summer vegetables longer. This would fill the gap when vegetables were scarce during the cold months of the year. Thousands of years ago the science of preserving would have been unknown, but adding salt to vegetables would have been a “light-bulb” moment. Another of these moments would have been the discovery that keeping the vegetables submerged in liquid prevented mould from forming on top of the ferment. Nothing has changed! These are still the principles that must be adhered to.

Fermented vegetables are easier to digest because they have been pre-digested by the microbes that ferment them.  The bacteria digest the carbohydrates and turn it into lactic acid – giving ferments their distinctive tangy taste. These are the bacteria that we naturally have in our gut and that add strength to our immune system. The nutrition in vegetables is increased with fermentation and our ability to absorb the nutrients is improved.

Try something simple to start with – perhaps a simple sauerkraut as below.

Sauerkraut  - recipe and picture from goodtoknow.co.uk

Immune System Boosting Kraut - this is my recipe and I love it. 

Beet Kvass - a drink which is possibly Ukranian in origin. Recipe and picture from TinandThymeUK

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