The Immunity Diet

by Colm O'Sullivan, on 24/05/21 10:50

In her new book, The Immunity Cookbook, nutritionist Kate Llewellyn-Waters explains the crucial link between gut health and immunity and provides evidence-based diet and lifestyle advice for supporting the immune system.  Read on for extracts of some of her key diet advice. 


There is no tissue or organ with a more significant influence on our health than the immune system. As well as fighting infection, our immune system has many other crucial functions, such as regulating body weight and metabolism, aiding the healing process, and even determining how we age. 

To live a healthy and happy life we need as strong and balanced immunity as possible, which can be achieved by focusing on adopting a nutrient-dense and balanced diet, exercising appropriately, ensuring sufficient sleep, and managing stress effectively. 

The link between the gut and the immune system  

The gut is a fascinating organ and, as scientific research shows, the health of our gut plays a central role in our immunity, since an astonishing 70 per cent of our immune cells live in the gut. 

Over the last ten years, it has become evident that the gut microbiome plays an important role in shaping the immune system, as well as contributing to health and disease. Our understanding of the gut microbiome is also increasing quickly, due to the development and application of technological advances, particularly genomic approaches. 

Nutrition to strengthen your immunity. 

A balanced and nutrient-dense diet is crucial to supporting our immune function. Research has shown that the development and optimal functioning of our immunity is directly influenced by diet. As well as ensuring healthy immunity, a balanced diet is also key for promoting optimal gut health.  

The immunity diet: Some key advice 

  1. Eat plenty of fibre-rich complex carbohydrates, such as oats, quinoa and brown rice. Fibre is a fantastic way to support immunity through your gut microbiome, while limiting refined sugar, as a high-sugar diet is harmful to our microbiomes. Bacteria love sugar, but if we consume a lot of sugar, the bacteria we don’t want more of in our guts are likely to multiply and potentially lead to dysbiosis. 
  2. Aim for at least 7 servings of vegetables and fruit a day (at least 5 vegetables and 2 fruit servings). Try to get 25–30 or more different veggies a week on your plate. 
  3. Protein is important for immunity, so include diverse protein sources in your diet and include plant-based proteins, such as lentils, quinoa, beans or tofu. (Do make sure you combine plant-protein sources, such as beans with rice, or lentils with rice, to ensure optimal protein quality). 
  4. Opt for fatty fish, such as wild salmon, sardines, trout or mackerel twice a week, or alternatively take an algae supplement if you don’t eat fish (choosing fish over red meat helps to reduce our saturated fat intake). Fish is also the number-one source of omega-3 fatty acids, particularly in the case of fatty fish. 
  5. Include at least 1 tablespoon of seeds or cold-pressed oil a day (olive oil or avocado oil over salads work well). 
  6. Add spices and herbs to dishes – as well as bringing delicious flavour, spices and herbs have antioxidant and anti-inflammatory properties. 
  7. Try to eat organically where possible, and always consume foods in their natural state

Find more advice and recipes in The Immunity Cookbook by Kate Llewellyn-Waters (Quadrille, £20) Photography ©Steven Joyce 

You can also try Kate’s prawn and fennel risotto recipe, designed to support both gut health and the immune system, here.

Visit our blog for more gut health tips and advice