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Gut Health

Immunity starts in the gut

Immunity starts in the gut
Eve Kalinik
Writer and expert1 year ago
View Eve Kalinik's profile

There are quite a number of impressive stats related to our gut such as we house some trillions, yes TRILLIONS, of microbes in our microbiome as well as the fact that we produce large amounts of neurotransmitters like serotonin, that have a role in our mood (see my previous blog post here for more on that). However, many of you might be really surprised to hear that the gut is our largest immune organ, accounting for around 70-80% of our immune cellular hard wiring in the body. Whilst we have other physical and mucosal barriers working to protect us including the skin and saliva most of our body’s natural Armour is located within the gut!

Here’s how it works…


Firstly, let’s look at GALT, or gut-associated lymphoid tissue, which is scattered throughout our gut and is an essential part of our gut’s immune system. GALT relies on intricate conversations between our gut microbiome and immune cells to distinguish friend from foe and act appropriately.

It is our gut microbiome that has a leading role including producing substances that it uses to signal directly to immune cells as well as providing a ‘boot camp’ to educate our immune cells to differentiate between beneficial and potentially pathogenic microbes. The role of the gut microbiome is therefore of paramount importance for healthy immune system regulation and why we need to take extra care to help nourish and support it.


The other crucial layer of the gut-immune link lies in the intestinal epithelial barrier which is just one cell thick. This barrier is essentially what separates our external world from our internal one and it also has a rather paradoxical role in that on one hand it needs to be permeable enough to extract the nutrients from our food but on the other it also needs to watch out for potentially harmful molecules. This is why we need to aim for a gut barrier that is both flexible and simultaneously vigilant.


Supporting a healthy gut-immune response is a multi-factorial process. Here’s some of the ways we can help this…

  • AIM FOR 30-PER-WEEK in terms of our plant food intake as this naturally increases our overall plant diversity which in turn supports a more diverse gut microbiome and immune system. This can be from vegetables, fruit, whole grains and nuts & seeds as well as spices and herbs. With this in mind consider making up nut & seed mixes that you can sprinkle over soups, salads, cooked vegetables, overnight oats and more. Vegetable boxes are another really easy way to get some natural rotation. Or try making my Plum & Hazelnut bars that includes 10 different types. Click here for the recipe
  • INCLUDE GUT NOURISHING FOODS - such as organic bone broth, fermented foods, all types of mushrooms especially the funkier ones like shiitake as well as pumpkin and sunflower seeds, Brazil nuts, salmon, mackerel, prawns, butternut squash, sweet potatoes, spinach, apples and spices such as turmeric that contain vitamins, minerals, polyphenols, amino acids and types of fibre that all help to support the health of the gut and the immune system. Try making up a stewed apple compote with cinnamon that you can serve alongside breakfast or as a tasty snack. Broths are also great in the winter months to give that instant feel good factor and here’s my Shiitake, leek and seaweed one if you want some inspiration
  • INCLUDE KEY CO-FACTOR NUTRIENTS such as vitamin C and zinc which are really important for the health of the immune system. Vitamin C is found in strawberries, kiwi, avocado, broccoli, rocket, all types of peppers, spinach and citrus fruit. The least cooked the better when it comes to vitamin C as it is impacted by heat. Zinc is abundant in shellfish, pumpkin seeds, hemp seeds, cashew nuts and traditional hard cheese which also includes a boost of beneficial bacteria for the gut too! Luckily Bimuno Immunity also contains both vitamin C and zinc to help meet your daily quota. And if you want a recipe that features a combination of some of the above check out my Panko crab cakes here


  • LET THE SUNSHINE IN as this is a key component of how our body makes vitamin D. Ideally aiming for 20 minutes of unexposed skin per day. This can be trickier in the winter months as the sunshine is not as strong so if you are living in the UK you may consider taking supplements. Furthermore, the benefits of being outside and in nature help us to manage the effects of stress which leads nicely onto the final point…
  • PRIORITISE REST as too much stress and not enough sleep can impinge on the health of our immune system. Allowing sufficient time before we go to bed without the devices in sight can help to cultivate a more restful nights sleep. Ideally aiming for an hour or so of winding down before hitting the pillow would be ideal. And alongside this try to include some kind of daily meditative practise such as breathing exercises, gentle yoga or straight up meditation has so many associated benefits including supporting the gut and the gut-immune link.


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Eve Kalinik
Writer and expert
View Eve Kalinik's profile
Eve Kalinik is a nutritional therapist, author & podcaster. As a specialist in gut health, Eve believes that having a healthy gut is fundamental to our overall well-being and thriving existence both physically and mentally. Eve’s passion and appreciation of how food makes us feel on different levels and her love to create delicious recipes to reflect this sentiment is why Bimuno loves to work in collaboration with Eve. Eve is a registered member of the IFM (Institute of Functional Medicine), British Association for Applied Nutrition & Nutritional Therapy (BANT) and the Complementary & Natural Healthcare Council (CNHC). She also holds a BA Hons degree in Psychology.