How is your immune fitness?

You'll likely have heard a lot of advice on boosting your immune system recently, but is constantly 'boosting' your immune system really the best course of action? The ‘fitness’ of our immune system and its resilience is far more essential in making sure we don’t tip the balance into a chronic inflammatory state...


Here I will be discussing some of the ways you can ‘exercise’ your immune system to stay fit and healthy by focusing on a type of immune cell that plays as a peacekeeper, known as the regulatory T cells. 

Why is immune fitness necessary?

One of your immune system’s vital functions is to regulate an appropriate immune response to molecules it comes into contact with by determining whether to initiate an inflammatory response against it. For example, on your skin, lungs and digestive tract, your immune cells will be exposed to food, bacteria, virus and pollutants, and it needs to make a decision: are these particles friend or foe? The correctness of this decision indicates your immune fitness. 

If your immune system misses a trick, you may end up with a nasty infection, allowing the bad guys to take hold of the opportunistic situation. However, suppose your immune system wrongly accuses a particle of wrongdoings. In that case, you end up with a negative response to something that might be beneficial, such as food and self tissue, leading to food intolerances and autoimmunity.

On the other hand, once the immune response has been triggered - for example, after an injury - another critical job of the immune system is to make sure that it responds appropriately and in a timely fashion. The exactitude of this response reveals your immune resilience.

Suppose your immune system stays switched on long after an inflammatory event. In that case, you are at risk of developing chronic illness, as low-grade systemic inflammation in your body contributes to damaging healthy cells, tissues and organs. 

Regulation of your immune response

Regulatory T cells, also known as T regs, play a pivotal role in immune fitness and resilience. The balance between a pro and anti-inflammatory response is essential for your health and wellbeing, and these cells are critical at maintaining this equilibrium. T reg helps neutralise a pro-inflammatory immune response through several pathways to ensure chronic inflammation is not pursued. 

An impaired regulatory response may arise for various reasons. Firstly, you may have a genetic susceptibility towards a pro-inflammatory state versus an anti-inflammatory state. However, as Mehmet Oz famously said, ‘your genetics load the gun. Your lifestyle pulls the trigger.’ So what lifestyle factors are at play?

Many scientists believe that a person’s lack of exposure to dirt and pathogens as a child may cause an undeveloped immune system in adult life, often referred to as the hygiene hypothesis. This lack of exposure means that your immune system hasn’t had the training that it needs to be in top shape for its adulthood challenge. 

Eating a standard Western diet of high sugar and unhealthy fats may also impact your gut microbiome’s microbiota composition. Beneficial bacteria and microbes in your digestive tract produce immune-modulating compounds which promote the T reg response. Ensuring that you eat a diet rich in various dietary fibres that keep your gut microbiome thriving is central to regulating the immune system and keeping it fit and healthy!

Obesity may also sway your body into a pro-inflammatory state, as adipose tissue in itself is inflammatory, releasing messengers known as cytokines to promote an inflammatory response. This effect of fat cells is why when someone loses weight, they often see improvements in their inflammatory symptoms.

How can you improve immune fitness and resilience?

If you do nothing else, having periods of fasting in your day and week could be the simplest way to start improving your immune fitness and resilience today. In a constant fed state, the T regs cannot properly develop and may cause a faulty and imbalanced immune system. Under the guidance of a qualified professional, you may want to explore intermittent fasting, where you eat within a shortened eating window, such as eight hours a day. Then, you could look to explore either a partial-fast or water fast for one to five days.

Vitamin D deficiency may also impact the regulatory T cell response, so get your levels checked. If your levels are low, make sure you go outside, expose your skin to the sunlight for 20 minutes a day (don't forget your SPF!) and eat vitamin D rich foods such as oily fish and egg yolks, or consider supplementing.

And lastly, if your body is stressed, nothing can function to its best, including your immune health. If you are struggling with stress, changes in mood or anxiety, then explore this first so you can build a robust immune system on solid foundations. Self-discovery and bringing joyful activities and people into your life are often significant first steps to emotional healing. 

So, the next time you recover from a cold, heal from a wound or feel full of energy, you can thank your immune system for its efforts and training. This silent system that works round the clock to keep you fit and healthy should receive this much-deserved recognition.

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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London W1G & Harrogate HG1
Written by V. J. Hamilton, Autoimmune Disease Expert | BSc (Immunology), DipION, mBANT
London W1G & Harrogate HG1

Victoria is a qualified Nutritional Therapist and member of BANT, focusing on autoimmune disease including skin disorders, heart disease and neurological issues, gut health and fatigue. Victoria has a BSc in Biochemistry & Immunology which she uses in her practice, using only science-backed nutritional therapies to support chronic conditions.

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