Five tips for building immunity today

By Dr Clare Bailey

Dr Clare Bailey and Dr Michael Mosley eating healthy veg to build their immunity

The recent outbreak of the Covid-19 coronavirus has shown us just how vulnerable we are to the emergence of new infectious diseases.

The spread of novel viruses is a particular challenge because we can’t rely on medicines to help us fight them. Our best defence is a fully active immune system.

Your immune system is a complex army of cells which are there to identify and destroy any potentially dangerous invaders such as bacteria and viruses. But to do this effectively the army needs to be in the best possible condition for combat.

Building immune-boosting habits is a sensible approach, particularly at a time like this when your health may be at risk. On top of the effective approaches to protecting yourself on the outside, like hand washing and social distancing, there are many small changes that you can make to help protect yourself from the inside.

1. Cook the Mediterranean way

One of the most powerful ways to boost your immune system is by eating a low-ish carb Mediterranean-style diet. This is widely seen as the healthiest, most nutrient-rich diet on the planet.

Not only is the Mediterranean diet high in health promoting nutrients, but the high fibre content is a great way to boost your gut microbiome. The “good” microbes convert the fibre into health promoting substances which are great at reducing inflammation and play a significant part in maintaining a healthy immune system. It also significantly helps you keep your blood sugars down in the normal range, which is important as having raised blood sugars reduces the ability to fight infection.

A diet rich in fresh vegetables, fruit, whole grains, lentils, beans, nuts, seeds, spices as well as fish, cheese and full-fat Greek yoghurt is not only delicious, it’s also highly nutritious. Curiously, most of these staples have been slower to disappear from the supermarket shelves than the less healthy white pasta, white rice and pre-cooked tinned foods.

And don’t worry that you should be eating fresh food. If you are having your vegetables, beans, fish from tins or frozen, that’s absolutely fine. The same applies to fruit but watch out for sugary syrup in tinned fruit. You still get the health benefits. Do make sure you are getting adequate fibre, best found in beans, lentils, wholegrains, which can easily be stored for many weeks also in tins, dried or pre-cooked sachets.

If you have to self-isolate, spending a bit more time cooking interesting and healthy food is also a great way to keep you active and improve your mood.

Michael and I have stocked up with a few extra tins of tuna and tinned tomatoes (apologies to other shoppers), dried lentils and beans, brown rice and quinoa, full fat egg mayo, some extra nuts, a few jars of anchovies, and two tins of dried milk and brown flour for bread. And of course plenty of olive oil. I plan to share some simple store cupboard recipes. And given that we have not been getting anything close to a Mediterranean level of sunlight, most of us are vitamin D deficient by this time of year, it may be wise to take Vitamin D supplements, known to boost the immune system.

2. Include fermented foods

We try to eat fermented foods, like kimchi, sauerkraut, kefir, sourdough bread, live yogurt and even some cheese on a daily basis. These probiotic-rich foods, which are also rich in vitamin C, iron and zinc, are known to boost the immune system and we love the tangy, sweet and salty flavours.

Nurturing a healthy gut microbiome doesn’t have to be difficult, but it does take some attention and it’s definitely worth it! We have a few favourite recipes to share including Kimchi Tofu Rice Bowl, Mushroom Omelette with Kimchi-style Sauerkraut, or the super simple Blueberry and Almond Yogurt.

If you happen to be confined indoors, you could start collecting jam jars and fill them with home-made fermented foods. It’s cheap, quick and easy to do and they are ready to eat in just over a week, but last for ages in the fridge.

Make time to try my super quick and easy Purple Sauerkraut!

3. Be active

Being fit and active will promote good blood circulation and help your immune system to do its job properly. Being confined to your home should certainly not be an excuse for not exercising. In fact, working out in your home is highly achievable and effective.

In addition to working out at home, I also love to get a good dose of fresh air. I have been doing an exercise class in the local park for the past few years, come rain or shine. And there is still plenty of space to keep your 2 metre distance. I also walk the dog daily and run two to three times a week, both of which are great for relaxation too.

4. Prioritise sleep

The benefits of a good night’s sleep are endless. A range of infection-fighting chemicals are released when you are in deep sleep. My husband, Dr Michael Mosley’s, latest book, Fast Asleep, which has just been published, is a great guide to improving your sleep. You can also learn more about why sleep is the foundation of healthy eating habits.

5. Manage stress

We know how important it is to try and reduce prolonged periods of stress. An increase in the stress hormone, cortisol, decreases the ability of our immune system to respond effectively to infections. Whilst it’s hard to avoid everyday stress all together, try and strike a balance.

Mindfulness, which might best be described as the ability to pay attention to the present in a non-judgmental way, has in recent years emerged as a highly effective way of handling stress. Michael has a breathing exercise which really helps:

Like many people, we’ve recently had to cancel our travel plans. Instead we are going to hunker down and adjust as necessary.


The Fast 800 is an innovative approach to healthy living and weight loss based on the latest scientific research. Developed in conjunction with Dr Michael Mosley, the online programme is for those that need more support and guidance for achieving long lasting health. If you join the online programme, you will receive Mediterranean-style menus with weekly HIIT and resistance training plans that are tailored to your level of fitness. 

Consult your healthcare professional and read our FAQs and medical disclaimer before beginning any diet or fitness regime.

Subscribe to our Newsletter