From A Nutritional Therapist

Hi, I’m Helen, Nutritional Therapist at Hedley Nutrition. I love cooking and eating good food (what Nutritionist doesn’t?). More importantly, I love knowing that as well as my food tasting great, it is doing good for my body and health too! I have a real passion for all aspects of Nutrition, but I find the immune system, the digestive system and nutrition for sports performance particularly interesting. I’m registered with the British Association for Nutrition and Lifestyle Medicine (BANT) plus the Complimentary and Natural Healthcare Council (CNCH).

Immune system function

So, one of my interests is the Immune System and I guess it’s something that is on everyone’s mind at present. The immune system is extremely complex and we’re still learning more about it. Basically, there are 2 parts to it; the innate part which is the bit we are born with and the adaptive part which learns to defend us as we encounter different viruses and bacteria. Once our bodies encounter an “invader” both parts help to mount the attack!  

T cells that from a vital part of our immune system are formed by the Thymus gland which, as Robert M. Sargis MD, PhD reveals is special in that, unlike most organs, it is at its largest in children perhaps leading to stronger viral immunity at a younger age.

The Immune system can’t be boosted, that’s a fallacy. Equally if you were to “boost” it that may lead to an over reaction which is basically what auto immune diseases are.

We often treat our health reactively; something goes wrong, so we do something to fix it. However, to help our immune system at this time we need to be proactive! So, how do we keep it in tip top condition?

Healthy immune system

While no food or drugs “boost” the immune system, there are ways to make sure we support a healthy immune response. Exercise, sleep and meditation can support a healthy immune response but here I shall focus in on how you can optimise your diet. Fasting is a whole topic in its own right, which we may dive into at a later date.


The basic advice is to ensure we consume a wholefood-based diet, rich in fruits, vegetables and wholegrains with small amounts of high welfare meat fish and dairy, some healthy fats like nuts, seeds and olive oil. With minimal processed foods, simple carbohydrates (cakes & biscuits etc) and sugar. You may feel like you’ve heard all this advice before, but for good reason, as it has proven results and can be easily accessible to all.


There are other things we can do too. Around 70% of our immune system is actually in our gut so supporting gut health is a top idea. Fibre is a great start; from wholegrains, pulses, fruits & vegetables, all are essential for healthy digestion. Not only does it provide bulk to keep things running smoothly, but the soluble fibre acts as food for the trillions of gut bacteria that inhabit our intestines and keep us healthy, not least by producing substances that help our immune system.

Many fruits and vegetables, such as bananas, leeks, garlic & onions are “prebiotics”, meaning they contain substances which further enhance the amount and variety of our gut bacteria. Besides garlic being an incredibly tasty herb Arlene Semeco, MS, RD lists how it is linked to various health benefits. Fermented foods such as yoghurt, kefir, sauerkraut, sourdough bread and aged cheese are fantastic foods for gut health as they contain even more healthy bacteria or “probiotics” to top up our microbial community. I recommend eating a little fermented food of some sort or another daily if you can. If you haven’t made it before, here’s a BBC recipe on how you can try making your own Saurkraut.


Fruits and vegetables provide a rich variety of vitamins and nutrients many of which are known for supporting the immune system. The government recommended 5 a day should be your minimum amount, but I’d recommend at least 7 portions a day. Make these 5 portions of vegetables and 2 fruits and you are getting an excellent range of nutrients whilst keeping sugar consumption under control. Go for as many different colours as possible each day for greater variety of vitamins and antioxidant phytonutrients such as flavonoids. 

We’ll take a quick tour around a few vitamins and where you can find them to make sure you’re getting what you need. Red & orange foods are rich in Beta Carotene, the precursor to vitamin A. Carrots, peppers cantaloupe melon, sweet potato, butternut squash are just a few I can list for you here. Leafy greens are rich in vitamin K but I’d rather not encourage their consumption as a high intake of vitamin K can interfere with blood thinning drugs, something to certainly consider if you have a medical condition. You’ll find Vitamin C in a mix of fruit and vegetables; the increasingly popular Kale, broccoli and infamous brussel sprouts are just a few to mention. Lemons, oranges and strawberries will also deliver you a healthy dose but just remember to be careful with your sugar consumption. Vitamin C & zinc can be consumed together and I’ll go into a little more detail on zinc in a moment.

Vitamin D has received a lot of press recently for its immunoregulatory effects. Vitamin D isn’t readily available in many foods. Those that do contain it are all of animal origin such as dairy, eggs and fish. It’s also made in the skin by sunlight but of course we need to keep covered or use SPF to protect ourselves from risk of skin cancer and ageing, so this is one situation where I would suggest considering a supplement, particularly if you are vegetarian or vegan. Supplements are not always as simple as they seem, so I recommend you seek advice from a registered nutritional professional or check the NHS website recommendations. Vitamin D deficiency among other lacking vitamins should generally not be sorted through supplement use especially as high doses of some supplements can have risks that Melinda Ratini, DO, MS warns us of.

Vitamins should ideally be sought through food first and only taken in isolation on expert advice (e.g. me) despite them being freely available to purchase. Supplementing without expert knowledge on the individual will at best waste money or at worst risk interactions with other drugs/supplements or overdose. Food first always!

Getting your intake from whole foods is best; all the nutrients work together rather than in isolation within your body, so you are getting them in their intended package. If you think you will struggle to eat that many portions a smoothie or smoothie bowl for breakfast is a great way to start the day – just remember, in this case, to keep the colours in your smoothie similar otherwise you will end up with something that might taste great but won’t look so appetising!


As well as eating more fruits and veggies, reducing the amount of meat you eat is also beneficial! However, when you do eat meat, ensure it is the highest quality you can afford; better quality meat means better quality nutrition. Meat is a great source of iron, needed for a healthy immune system although we don’t need too much of it. The iron contained in red meat is more readily absorbed by the body than vegetarian sources of iron. If you are vegetarian then combining your sources of vegetarian iron with vitamin C will help absorption, as will avoiding foods high in tannins such as tea which block absorption.

Add in a few portions of oily fish and some seafood for zinc and Omega 3. Oily fish like salmon, mackerel, anchovies, sardines and herring are rich in Omega 3 oils. These oils have an anti-inflammatory action in our bodies which helps keep our immune system balanced by reducing any inflammation we don’t need. Seafood is also an excellent source of Zinc, another key component of our immune system. Not a fan of fish? Then add a variety of nuts and seeds to your diet instead. Nuts such as walnuts and cashews and seeds like chia, pumpkin, sesame and sunflower are fantastic snacks or sprinkle over soups, salads and even smoothie bowls! Among the wonderful selection of produce our grocers list you may find the Chia Round Loaf. Kris Gunnars, BSc explains that in addition to being loaded with fiber and omega-3s, chia seeds are also packed with minerals

Whole grains

Whole grains are healthy due to their fibre content and more nutrient content in the “whole grain” or Husk. For example brown rice is higher in vitamin B1/Thiamine than white as the vitamins are contained in the Husk.

Bread as a food group isn’t specifically whole grain but can be depending on what you are picking up from the shop. Think wholegrain and wholemeal bread over white bread, wholegrain spelt bread, malthouse bread with added grains etc. It is useful to check that it is 100% wholegrain opposed to partly included. 

Nuts aren’t actually whole grain as some may think, nuts are classed as a seed except peanuts which are a legume (bean) but can still provide their own health benefits as mentioned.


I often get asked whether Tea contains antioxidant and the answer is yes as does coffee, so don’t feel too bad when you’re having a nice warm cuppa. Do consider the effects over drinking too much though! Lemon as all fruit & veg are also antioxidants and these can all add to your overall antioxidant intake. Iron isn’t an antioxidant, to get a little more geeky than perhaps I already have, an antioxidant is specifically a compound that can donate an electron from its outer shell to make another electron become stable whilst remaining stable itself. 

Antioxidants fight free radicals in your body. These compounds that can cause harm if their levels become too high in your body. They’re linked to multiple illnesses, including diabetes, heart disease, and cancer.

Any Other Boosts?

As well as eating good food, your lifestyle choices will affect your immunity. Dealing with stress and anxiety through meditation and mindfulness, taking regular exercise and getting at least 7 hours of restful sleep, have all been proven to support immune function.

My last tip? Keep things in balance – remember to enjoy all foods and that includes the occasional chocolate brownie or Eccles Cake (my favourite)!! 

The advice contained in this article is just generalised. We are all individual and therefore require individual nutrition and dietary support for our health. If you have any specific health questions or nutrition concerns then please see for a complementary chat about how I may be able to help.