Winter brings shorter days, colder temperatures, and an increased exposure to seasonal bugs. Our immune system is an amazing collection of unique organs and cells that plays a crucial role in protecting the body against external invaders, including the bacteria and viruses that are so rife this time of year! 

While we can’t make our immune system invincible overnight, there are practical, evidence-based steps we can take to help our bodies stay resilient. This article explores five simple yet powerful ways to “health hack” your immune system, covering nutrition, hydration, gut health, key nutrients, and lifestyle habits, so you can feel your best and keep your defences strong all season long. 

Eat A Nutrient-Dense Diet

Eating a balanced, nutrient-rich diet that provides a range of macro- and micro-nutrients is key to supporting a healthy immune system. You should base your plate around the following nourishing foods: 

Protein-rich foods

Lean meats, fish, eggs, legumes, and nuts are great sources of protein, which is required to make antibodies and for immune cell function, as well as having antiviral properties.

Healthy fats

Omega-3 fatty acids, found in foods such as oily fish, chia and flaxseeds help to support anti-inflammatory pathways, preventing chronic inflammation, which can impair immunity. Omega-3s also support the structure and function of immune cells, allowing them to signal to each other to respond effectively to pathogens. 

Eating the rainbow

Enjoying a wide range of colourful fruits and vegetables each day is the best way to up your intake of phytonutrients: protective plant compounds that contribute to the vibrant colours in these foods. Each colour brings its own unique set of phytonutrients which work together to strengthen immunity – so variety is key! Plant foods are also amazing sources of vitamins and minerals such as vitamin C, B vitamins, selenium and zinc, which are essential for optimal immune health.

Include herbs and spices 

as well adding a flavour-punch to your meals, these ingredients can be powerful allies for your immune health. Warming spices like turmeric, ginger and cloves can all help to reduce inflammatory markers and support a balanced immune response. Herbs such as garlic, oregano and thyme contain compounds that exhibit antiviral and antibacterial activity. Get creative with your cooking to support your immune health!

It’s also important to be mindful of foods that can impair your immune function and avoid them where possible. Foods high in added sugar, refined carbohydrates, and trans fats, such as sweets, pastries, white bread, and fried or ultra-processed foods can promote inflammation, disrupt gut health, and increase the risk of infections and illness. 

Stay Hydrated

Support your gut health – your first line of defence.

Did you know around 70% of your immune tissue lives in your gut? This area, called the gut-associated lymphoid tissue (GALT), acts as a protective barrier against harmful bacteria, viruses, and toxins that enter through food and the environment. Your gut lining has a large surface area (about the size of a tennis court) and it’s constantly working to keep you protected and healthy, so it should always be a key focus when thinking about supporting optimal immunity.  

Probiotics 

Live bacteria supplements, known as probiotics, can help restore balance in your gut by encouraging healthy microbes and preventing harmful ones from taking hold and growing. Extensive research has demonstrated the beneficial effects of probiotics for immune health including vitamin synthesis, inhibition of growth and colonisation of pathogenic bacteria, antimicrobial activity and supporting the immune responses via secretory IgA antibodies.¹

Prebiotics 

Prebiotics are dietary fibres which act as food for the microbiota and stimulate the growth of beneficial bacteria. The digestion, or fermentation, of these “prebiotics” produces short chain fatty acids (SCFAs), which act as a fuel for the cells lining the digestive system, known as enterocytes, and support the integrity of the digestive lining. SCFAs enhance the production of mucin; a gel-like substance that creates a protective layer in the gut to help block harmful microbes and support immune defences by maintaining a strong barrier against infection.  

Support your gut through diet: 

Targeted Nutrients & Supplements

There are a number of nutrients that can support your immune health to protect you against viruses, as well as help your recovery if you do fall ill. 

Vitamin A 

This fat-soluble vitamin is important for the normal function of the immune system through its role in the formation of immune cells such as antibodies and T Cells; the type of white blood cells that help identify pathogens. It also plays an important role in the maintenance and repair of the body’s natural defences, which includes the mucosal barriers in the respiratory and digestive tract. These help to trap bacteria, viruses and other infectious agents. 

Vitamin C

Has been shown to be supportive for several different immune cells. It can support the production and function of white blood cells, which can protect us against infection. Vitamin C also has antimicrobial properties, to inhibit the growth of unfriendly bacteria, and can help to prevent and reduce the duration of respiratory infections. 

Vitamin D

Known as the “sunshine vitamin”, vitamin D can profoundly strengthen both our innate and adaptive immunity, and several different immune cells have vitamin D receptors that affect their function. It can also play an important role in modulating the immune system, ensuring its appropriate function and reducing the chance of developing allergies and auto-immunity. Sub-optimal levels are common in the UK, particularly over winter. 

Zinc

Is essential for the normal development and function of immune cells, and a deficiency in zinc can impair immune function and leave you more susceptible to infection. Research shows that taking zinc at the start of a cold can shorten its duration.

Beta Glucans 1-3, 1-6

Found in a limited number of foods, is known to have a “priming” action, which readies the immune system to fend off harmful pathogens.

Lysine 

This amino acid aids antibody production and tissue repair. Lysine also exhibits antiviral properties by inhibiting viral replication

N-Acetyl Cysteine (NAC)

Another amino acid which has shown great promise in respiratory and overall immune health. NAC helps to relieve respiratory symptoms by reducing inflammation and loosening mucous in the airways, thereby improving overall lung function.

Elderberry 

Supplementating with this superfood has been associated with shorter duration and reduced severity of cold and flu symptoms. Elderberry is rich in phytonutrients, such as anthocyanins that may inhibit viral replication, modulate cytokine activity to reduce inflammation and provide antioxidant support.

Prioritise Healthy Habits 

There are also a number of lifestyle choices you can make to support optimal immune health: 

Sleep

Sleep is crucial for a healthy immune system because it's when the body produces protective cytokines, repairs cells, and strengthens immune responses to fight off infection. Lack of sleep can lower immune function and increase susceptibility to illness.² Aim for 7-9 hours of refreshing sleep each night and practice great sleep hygiene to ensure quality shut eye.

Movement

Moderate exercise sessions (under 60 minutes) can boost your immune system by improving circulation of key immune cells like natural killer cells, T cells, and antibodies. These short bouts of activity enhance your body’s ability to detect and fight pathogens, reducing the risk of infections such as colds and flu. Regular physical activity also supports gut health, which as we know is vital for immunity.³

Stress Management

Stress triggers the release of hormones like cortisol and adrenaline, which are helpful in short bursts but harmful when elevated for long periods. Chronic stress can suppress immune function by reducing the activity of natural killer cells, impairing antibody production, and increasing inflammation. This makes the body more vulnerable to infections and slows healing. Managing stress through relaxation techniques, good sleep, and healthy habits is key to keeping your immune system strong.⁴

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