Your immune system is made up of a network of cells, tissues, organs, and chemicals. You have your innate (first-line defense) and adaptive (acquired, second-line defence) immune systems. These both  play a crucial role in your susceptibility, persistence and clearance of disease.

Whilst we cannot “boost” our immune system, as much of the internet will claim, we CAN support and optimise its function.

So let’s tackle 5 tips to boost your immunity 😉

1. Good quality sleep (7-9 hours a night)

Sleep is essential for optimal immune function. The inflammatory response is the body’s natural response to injury or illness, regulated by cytokines (immune proteins) to initiate repair. During sleep, there is an increase in the production of sleep-regulatory cytokines, strengthening innate and adaptive immunity. Just as we need sleep to consolidate our learning and memories, our immune system requires sleep to strengthen immune memory and our ability to respond to pathogens more efficiently in the future.

• Just one night of 4-hour sleep reduces natural killer cell (white blood cell) by 70%!
• When we compare 5 hours to 7 hours of sleep, for 5 nights, before catching rhiovirus... you are 4x more likely to develop the flu if you only slept 5 hours... are you always complaining of being sick?

2. Get outside! Top up your Sunshine vitamin

Vitamin D is produced in our skin in response to sunlight. It acts more like a hormone than a vitamin in the body, and binds to Vitamin D receptors. Vitamin D receptors are found throughout the entire body, showing its significance in human health and our susceptibility to infection.

Cells of the immune system synthesize and respond to Vitamin D. For example, it affects the body’s ability to mature and activate T cells (another white blood cell), favouring an increase in the production of anti-inflammatory cytokines and a decrease in the production of pro-inflammatory cytokines. This helps our body fight infections, promote apoptosis (cell death) and suppress inflammation in the gut (where much of our immune system lives).

• Ensure your skin feels sunlight at least 3x a week for 15 minutes, with no protection (long sleeves, sunscreen, etc.). If this isn’t available to you, consider supplementing with a good quality Vitamin D3 or Cod Liver Oil.

3. Get active! Movement is good for the body and the mind 

Exercise enhances the immune system. Moderate-intensity physical activity stimulates cell-mediated immunity (the protective processes), while prolonged or high-intensity exercise without adequate rest can suppress immune function.

For example, the right amount of exercise increases blood flow, core body temperature and the release of beneficial immune cells, to help your body fight infections, decrease chronic pro-inflammatory responses and improve systemic (whole-body) inflammatory processes. Exercise is also a well-known stress release due to the release of feel-good neurotransmitters (brain chemicals) known as endorphins.

• A decrease in immunity happens at around 90 minutes of moderate- to high-intensity exercise. A brisk 30–45-minute walk three times a week is a great start! Or lifting weights twice a week for 45-60 minutes, depending on your level of experience.

4. Practice mindfulness in your own way

We all know stress wreaks havoc on our bodies... In a normal response, cortisol is increased to help us deal with stress. In prolonged stress, cortisol can remain high and weaken our immune system through chronic immune activation. High levels of immune activation, particularly inflammatory cells, can cause chronic, low-grade inflammation, shown in the development of mental health illnesses, gut conditions, cardiovascular disease and autoimmunity.

• Following on from the previous tip, exercise is an excellent mood booster and stress release tool. Plus, it’s free! Take a walk outside, a swim in the sea or find hundreds of videos on YouTube to follow – the options are endless. YouTube is also a great resource for mindfulness and meditation videos. Mindfulness meditation reduces pro-inflammatory processes and increases cell-mediated responses.

5. My personal favourite - nourishing your body with the right nutrients

With around 70-80% of our immune cells found in the gut, should we be looking more closely at supporting our gut health, to support our immune health? There is now a well-established link between what we eat and the composition of our gut microbiota. These immune cells are found in gut-associated lymphoid tissue (GALT).

The foods you eat can affect your microbiome, your gut barrier, inflammation and white blood cells (your immune cells). Eating a range of whole foods provides nutrients such as vitamin A, the B’s C, D, E, trace minerals, essential fatty acids and amino acids. These nutrients are essential in supporting your immune system, reducing oxidative damage and inflammation and reducing your risk of infection.

• Aim for 5 serves of vegetables and 2 serves of fruit a day, oily fish (salmon, mackerel, sardines, cod) at least twice a week, a range of plant and lean animal proteins and don’t forget hydration! One serving of vegetables is considered 1 cup of leafy greens, or half a cup of dense vegetables such as broccoli, beetroot, carrot etc. Try to eat different colours to consume a range of nutrients.

References:

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