Look after the Inside to Thrive against the Outside

We are currently in the midst of a viral pandemic that is causing global hysteria, and posing a challenge to both our physical and mental health. We are being forced to take extreme measures to control the spread of this novel virus, which are primarily focused on controlling our external environment. Unfortunately, there seems to be very little mainstream focus on what we can do to optimize our internal environments and natural defence mechanisms, which is one of the most important factors in our ability to survive and thrive against this, and many other infections.

The French Physiologist Claude Bernard argued that ‘the microbe is nothing and the terrain is everything’, which even his contemporary Louis Pasteur is thought to have admitted in his final days. This translates to the theory that we become more susceptible to infectious agents when the body’s balance or homeostasis is disturbed.

Unfortunately, ever increasing rates of conditions such as obesity and type 2 diabetes are destroying our body’s homeostasis, compromising our immune systems and  leaving our ‘terrain’ more vulnerable to microbes. Therefore, optimising our inner ‘environment’ is just as, if not more important than trying to sanitise and control our external environment.  In reality, there are numerous potentially harmful microbes inhabiting our whole body and environment all day every day, so if our health depended on avoidance of bacteria and viruses, we wouldn’t be the successful and abundant species that we are today. 

What is our immune system?

Our immune system is made up of many parts of our body including various cells, proteins, lymphatic system, spleen, bone marrow, thymus and our digestive system. In addition, our skin, body fluids and the lining of our lungs are constantly working to protect us from the many viruses, bacteria and pathogens that we are coming into contact with on a daily basis.

We possess a highly effective front line of defences made up of a variety of receptors, proteins and cells that are vigilantly patrolling our bodies to recognize signs of infection, launch appropriate responses to eradicate offensive pathogens, and then equip us with the resources to protect us against any future encounters.

The gut barrier

Our digestive system is the area of our body that is faced with the greatest toxic load, such as bacteria, funghi and viruses. This is due to the billions of bacteria in our colon and a variety of toxins in the foods we eat. Our gut also houses a significant proportion of our immune system and provides us with an effective response to any invaders when needed.

In order to maintain proper function, our immune defences cooperate with the billions of bacteria in our digestive system known as our gut microbiota. Our gut bacteria enhances our immune defence, and we in turn provide the bacteria with a home. 

If our gut barrier isn’t functioning well we can launch inappropriate immune responses to innocuous food and bacteria that cause excessive inflammation. These exaggerated immune and inflammatory responses contribute to conditions such as inflammatory bowel, crohn’s and coeliac disease.  A compromised gut barrier has also been linked to autoimmune conditions such as Rheumatoid Arthritis and Multiple Sclerosis.

Our immune system is influenced by our daily habits

The vast majority of us have great potential to influence how well our immune system functions and protects us. Unfortunately many people believe that the state of our health is governed by what we inherit from our parents, and that we have little control over whatever bugs and infections ail us. It’s very common to hear people blaming whatever is ‘going round’ when they feel under the weather, when in reality we should stop and think about how we may have become susceptible to any pathogen that has compromised our immune barrier. 

Our individual immune systems are unique and change day to day depending on how we eat, sleep, move and respond to stress. Therefore, we will all respond differently to dis-ease. We all have and will express genes that allow us to deal with certain viruses and bacteria better than others. Our immune defences are influenced not only by our genetic inheritance, but also by our daily habits and how we interact with our environment.

The hygiene hypothesis has clearly proved that people who are exposed to more germs, through living in bigger families or living in dirtier environments, suffer less allergies, asthma and hay fever than those living in more sterile environments. This is an example of how we can influence the function of our immune system, and how our day to day environments and habits can either bolster or weaken our defences.

One of the most significant, if not the most significant contribution to our immune system happens during natural childbirth. During the vaginal delivery, the digestive system is colonized with bacteria that informs and shapes our immune system. Babies exposed to their mother’s bacteria through natural child birth tend to have better immune function than children born by caesarean section, who are more likely to suffer from allergies, chronic inflammatory and metabolic diseases. 

The mutual struggle between virus and host.

We are living amongst potentially pathogenic viruses and bacteria everyday of our lives and have done since the dawn of mankind. We are breathing in millions of virus and bacteria like particles every day, in both our indoor and outdoor environments. Our natural defences are in a constant ‘arms race’ with viruses and bacteria, which are constantly evolving in order to evade our immune system defences, latch onto our cells and replicate.

Viruses are highly adaptable strands of genetic material  in a protein shell that infect living cells. In some cases they can avoid detection by our immune defences and also disarm our built in antiviral immune responses. It’s actually not in the interest of viruses to do too much harm to us because we are better at helping them spread and multiply if we are alive! However, some viruses have, and still do, prove to be deadly in a small percentage of the human population. 

There are thought to be over 200 species of virus that are able to affect humans, with new ones being found every year. Theories about the drivers behind the emergence of new viruses include population growth, increasing urbanization, global travel and trade, and intensifying livestock production. 

There are many theories about how viruses first emerged, but the bottom line is that they have been around a lot longer than we have. Viruses have played a key role in the evolution of cells and therefore us as human beings! Some are actually protective, and regarded as more effective than antibiotics. This demonstrates the symbiotic relationship and struggle between us (the hosts) and viruses, that will probably continue throughout mankind. It also highlights the need for us as individuals to do what we can to ensure that our defences are in the best shape possible to cope with these ever-evolving pathogens

So what can we do?

As thankful as I am for the wonders of modern medicine, the focus of our conventional healthcare system is more geared toward managing disease and destroying pathogens, rather than strengthening our defences against them. Unfortunately, in many cases, the destruction of pathogens (especially anti-biotics) weakens our immune defences in the process. 

Protecting our health and bolstering our defences begins much further upstream than the advent of symptoms, and the most effective application of healthcare is through the medium of food, movement, stress resilience, rest and interaction with our day to day environments. Being proactive with our health before illness sets in, instead of reacting when it does, will improve our capacity to manage and recover from viruses and infections, far more effectively than any pharmaceutical medication. 

It’s important to remember that there is a multi billion dollar industry encouraging us to rely on pharmaceutical medicine rather than rely on, and strengthen, our own natural defences!

As mentioned earlier, a significant part of our immune system is housed in our digestive system, and Is the place where we are exposed to most toxins and foreign substances in the body. It’s the job of the intestinal immune system to distinguish between non-harmful food and bacteria and harmful pathogenic micro-organisms. 

There are thought to be between 1000-1500 different types of bacteria in the human gut. This diversity is strongly influenced by our lifestyle, and especially our diet. Consuming a typical western diet containing fried foods, sugary drinks, pastries, cakes, processed meats and desserts, reduces the diversity of our gut bacteria.

 A more diverse range of bacteria in the gut is considered healthy due to the many health benefits a greater number of species can provide.

One of the most effective ways to improve the number of beneficial bacteria in our digestive system is to eat a diverse range of whole or naturally occurring foods such as fruit, veggies and legumes. 

We only need to look at the common characteristics of the inhabitants of the blue zones around the world to acknowledge the benefits of a predominantly plant-based diet. 

Eat Prebiotic Foods

For gut health and immune function we should be trying to eat as many prebiotic foods as possible. Pre-biotic foods help to feed our good bacteria, and are defined as non-digestible food ingredients that improve our health by selectively promoting the growth of various bacteria in the colon. The majority of these ingredients are in the form of fibre, which avoid digestion and produce fuel for our good gut bugs.

Prebiotics also: 

Some of the most common prebiotic foods include:

  • Onions
  • Chicory root
  • Leeks
  • Garlic
  • Oats
  • Artichokes
  • Bananas
  • Asparagus
  • Apples
  • Flaxseed
  • Barley
  • Wheat Bran (outer layer of the whole wheat grain)

Eat Foods containing Probiotics

Probiotics are actually live strains of bacteria that may provide benefits when eaten in adequate amounts. Some of the most common species of probiotics are Lactobacilli and bifidobacteria which can be found in foods such as unpasteurized sauerkraut, kimchi, kefir, yoghurt, cheese and pickles.

Eat foods that are high in Polyphenols

Polyphenols are plant compounds that have many health benefits, including reductions in blood pressure, inflammation, cholesterol levels and oxidative stress

Polyphenols can’t always be digested by human cells. Given that they aren’t absorbed efficiently, most make their way to the colon, where they can be digested by gut bacteria 

Good sources of polyphenols include: 

  • Cocoa and dark chocolate
  • Grape skins
  • Green tea
  • Almonds
  • Onions
  • Blueberries
  • Broccoli

Polyphenols from cocoa can increase the quantity of beneficial bacteria in our gut and reduce the quantity of potential harmful ones.

Eat foods that are high in specific micronutrients

Foods high in vitamins A, C, D, E, folic acid, selenium, iron, and zinc, will all contribute to a optimally functioning immune system. A varied diet containing citrus fruits, green leafy vegetables, orange coloured veg such as squash, sweet potato and pumpkin, oily fish, nuts, liver, eggs and seafood will help keep your defences strong against ever-present bugs and nasties.

Essentials for aiding recovery

Vitamin A is particularly crucial for enhancing immune function. The best sources are from liver, cod liver oil and oily fish.

Zinc is also another essential micronutrient for the immune system. The best sources are meat, seafood, legumes, nuts and seeds. Zinc acetate lozenges have shown to be effective in significantly shortening the duration of viral infection of the upper respiratory tract.

Black Elderberry is a type of food containing high amounts of vitamin C, fibre and many health protective antioxidants, which have shown promising results in the treatment of viral symptoms

Vitamin D not only contributes to a stronger immune system, it may also protect against seasonal influenza. Research suggests that up to half of the world’s population may be deficient in vitamin D. Even people in countries with sunlight all year round produce low levels of vitamin D, due to things such as working indoors and covering up.

 Sunshine is the best way to get your vitamin D, so a good 20 minutes per day of  exposure, on as much of the body as possible, is recommended. If you can’t get sunshine, supplementing (good one here) would be the next best thing. If you’re unsure about your vitamin D levels, you can go for a simple 25(OH)D blood test. Low levels are common in older people and those with darker skin.

Older people tend to suffer from more respiratory and genitourinary infections due to dietary deficiencies in nutrients such as vitamins A, C, D, E and zinc. As we age our skin becomes less efficient at producing vitamin D from the sun and we tend to eat less volume and variety of foods.

Foods to avoid

A diet high in refined carbohydrates and sugar, low quality fats such as hydrogenated fats, and seed oils have been associated with increased inflammation and unfavourable changes in the gut. Artificial sweeteners can also reduce the diversity of our gut bacteria.

From a very basic standpoint, we should be trying to eat as much naturally occurring or what I regard as ‘real’ food as possible. In times like this, If you look down at your shopping trolley and see an abundance of foods that are made in a factory with industrial ingredients and additives, think about whether you may be harming or helping your immune system with what you’re eating.

As well as eating the right foods we also need to consider other areas of our life that can have a significant impact on our immune defences.

Limit use of antibiotics

The overuse of antibiotics can cause resistance and also kill our resident bacteria that combat infections and inflammation. Although antibiotics are very good at preventing and treating some bacterial infections, they can reduce the amount and diversity of gut bacteria which may actually weaken our immune defences against certain viruses.

Get regular exercise

Regular moderate to vigorous exercise bouts of below 60 mins have been shown to have an immune boosting effect. Exercise also has an anti-inflammatory and antioxidant effect, protecting us from conditions such as cancer, heart disease, flu and pneumonia. In addition to this, exercise contributes to a more diverse gut bacteria. As mentioned earlier, our immune system becomes weaker as we age, however habitual exercise can delay this decline and protect us in later life.

Get outdoors in some sunshine

Top up your levels of immune protective Vitamin D, regulate your sleep, and get some fresh air in your lungs. It just makes sense!

Practice Intermittent Fasting

Fasting anywhere between around 16 – 48 hrs can enhance the production of immune cells and raise blood levels of ketone bodies. These ketone bodies replace glucose as the primary source of fuel, and also act as signalling molecules which help reduce inflammation, blood pressure, cancer, heart disease, neurodegenerative disorders and autoimmune conditions such as rheumatoid arthritis and multiple sclerosis. 

If you’re not used to fasting start by reducing your eating windows to 8-10 hrs for a week or 2 before attempting  a 24 or 48 hr fast. 

Have a good giggle

Having a good old belly laugh reduces stress, increases our oxygen uptake and the production of natural killer cells which help fight viruses. 

Get in line with your circadian rhythm

Prioritise your sleep and try to achieve a quality 7-8 hrs sleep per day,


Evidence from brain imaging studies has shown that long and regular breathing alongside meditation significantly deactivates the limbic system. The limbic system is one of the most primitive parts of the brain, primarily responsible for activating the fight or flight response. Breathing causes fluctuations in our blood pressure, which increases during Inhalation and decreases during exhalation.

Slow diaphragmatic breathing is associated with reduced blood pressure, improved circulation, cognitive performance, sustained attention, breathing efficiency and parasympathetic dominance (a calmer nervous system).

A pattern of 5-6 breaths per minute has been shown to reduce feelings of anxiety and significantly increase feelings of relaxation. This includes an inhale/exhale ratio of 5 seconds in/5 seconds out. A Diaphragmatic breathing rate of 6-10 breaths per min is considered to be an optimal range.

Chill out and keep things in context

We are the most successful species on earth, and with that privilege we are inevitably going to continue to be moulded and shaped by pathogens that adapt and evolve quicker than us and have been here a lot longer than us. Bacteria, viruses and pathogens have quite literally shaped the world we live in. 

Chronic or ongoing stress inhibits our immune defences, so with regard to the coronavirus, try to make a concerted effort to pay attention to all the positive developments happening around the world, and how people and societies are recovering and bringing the virus under control. In situations like this, it may be useful to be aware of our inbuilt negativity bias

Control your Negativity Bias

We are evolutionarily primed to place more value and attention on negative information than positive information. After all, being more vigilant and attentive towards negative stimuli around us such as predators, helped keep our ancestors alive! This bias towards negative stimuli keeps us safe and out of danger. This is why we tend to dwell on unpleasant experiences more than pleasant ones, and focus more quickly on negative information. This is also a reason why news coverage is also predominantly negative.

Negative coverage is more attention grabbing than positive coverage!

We are all united in this global experience of apprehension and unpredictability so try to maintain an optimistic perspective, and although we are being encouraged to practice physical distancing, be sure to stay socially connected. 

Take some of this forced downtime to deliberately start the day with a sense of gratitude for some of the most fundamental and simple things in life. In addition, cultivate a greater sense of humbleness and humility in the knowledge that life is a gift, and as humans, we belong here no more than any other plant or creature on this planet.

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