Is it possible to Boost your Immune System during Covid 19?

This is the season where the temperature starts to drop and flu season starts to well and truly kick in. Colds, runny noses, sore throats are par for the course so during this time it is important to try and keep our health and improve our immunity. The Corona virus outbreak had us all googling ways in which we could ‘boost our immunity’.
So what exactly is ‘your immunity?’
Your immune system is made up of your bodies defence against infection and illness. It basically operates like a defence system that fights off an unfamiliar germs, bacteria or parasites. These cells operate best when they are in balance and harmony!
Can we boost our immunity?
Whilst this is an enticing idea there has been no scientific evidence to suggest we can improve the number of immune cells (white blood cells) in our body (lymphocytes and phagocytes). We can rather bolster our protection against harmful viruses and bacteria by adopting some healthy living strategies such as:
– Eating a diet high in fruit and vegetables
– Not smoking
– Maintaining a healthy weight
– Exercising regularly
– Drinking alcohol in moderation
– Practicing proper hygiene such as hand washing and cooking meats thoroughly
– Getting enough sleep
– Trying to minimise stress

1. Fresh fruits and Vegetables:

What we do know is that the greater our intake of brightly coloured fresh fruits and vegetables, the better our health, weight and immune function. Fresh fruits and vegetables are packed full of vitamins and minerals, many of which play crucial roles in our daily immune functioning. Some nutrients such as vitamin C, have specific roles in fighting off bugs and keeping our cells healthy.
To optimise our immune system we need at least 5 serves of vegetables and 2 serves of fruit each day for good health, but when it comes to optimal immune function, 10 serves a day is a good target. Ten is the magic number of 80 gram serves of fruit and vegetables you should eat every day to most dramatically lower your risk of disease and death, says the Imperial College of London. That adds up to 800 grams per day of the healthy stuff!
When it comes to our meals and snacks every main meal should contain a palm size amount of whole protein (meat, fish, eggs, dairy, beans or lentils), a healthy fat (nuts, olive oil or avocado) and a variety of colourful vegetables . Mix up your colours as well as enjoying both fresh and cooked options to ensure you get a range of different nutrients from different foods. Try to incorporate a range of salads or fresh juices and grab a piece of fruit as a snack. Eating at regular times throughout the day will also support your adrenal health and balance your hormones.
Broccoli: is packed full of phenolic compounds, powerful anti-oxidants and anti inflammatories that reduce the risk or coronary heart disease, Type 2 diabetes and asthma and keeps your cells young.
Vitamin D: you get from the sun, fatty fish, eggs or supplements. Studies have found that it does everything from improving strength in muscle and cognitive function to benefiting gut flora and preventing respiratory infections.
Fish Oil/Omega 3: can reduce the effects of a high fat diet by fighting the inflammation this causes by, spread the clearance of waste from the brain and reduce the risk of cardiovascular disease.
Magnesium: great for heart health like arrhythmias and hypertension to atherosclerosis and endothelial dysfunction.
Tumeric: an anti inflammatory and anti-oxidant that makes it a potent protector against cancers and ageing free radicals. It also improves brain function and lowers the risk of heart disease, Alzheimer’s and depression.
Walnuts: high in vitamin B, fibre and omega-3 fatty acids, walnuts are packed with phenolic acids, tannins and flavonoids. They boost brain power, reduce cardio vascular problems and help prevent Type 2 diabetes, obesity and Alzheimer’s disease.
Vitamin C: foods which are packed full of vitamin C include oranges, kiwi fruits, berries, tomatoes and red capsicums. They are full of anti-oxidants which offer positive nutritional benefits.
Garlic: helps to stimulate the production of macrophages (immune cells) in conjunction with vitamin D.
Iron and Zinc: are required to support proper immune function, and a deficiency may impair the ability of the immune system to ward off illness. Iron regulates cell growth and differentiation and is a structural component of many proteins and enzymes.

2. Exercise Regularly:

Just like a healthy diet, exercise can contribute to general good health and therefore to a healthy immune system. According to ‘Harvard Health Publishing’ (2014)

“it may contribute even more directly by promoting good circulation, which allows the cells and substances of the immune system to move through the body freely and do their job efficiently’.

Studies have also been conducted into whether there is a link between elite athletes undergoing intense physical exertion and whether they are susceptible to a weakened immune system. For now, even though a direct link has not been established, it’s important to recognise that moderate regular exercise is the best course of action of healthy living and keeping your immune system in check.
Australia’s physical activity guidelines according to “The Australian Government Dept. of Health’ website states that adults between the ages of 18 to 64 should be active on most days preferably everyday of the week. Accumulate 150-300 minutes (2 ½ hours to 5 hours) of moderate physical activity and or 75 to 150 minutes (1 ¼ to 2 ½ hours) of vigorous intense activity, or an equivalent combination of both vigorous or moderate activities each week. Try to incorporate muscle strengthening activities at least 2 times per week.
Try to include incidental exercise like taking the stairs, walking to work, getting up from your desk every 30minutes and walking around. This makes a big difference to our health and wellbeing.

3. Stress and Immune Function:

Chronic stress or long term stress has been proven to depress the immune system and increases the risk of several types of illnesses such as digestive problems, increased heart rate, hypertension, and elevated cholesterol levels. Chronic stress raises the level of catecholamines. According to (2015):

“These hormones are released in response to physical or emotional stress. Catecholamines are hormones produced by the adrenal glands, which sit on top of the kidneys. … Catecholamines are released into the bloodstream when you’re physically or emotionally stressed”.

Being stressed out leads to increased levels of suppressor T cells, which suppress the immune system. When this branch of the immune system is impaired, you are more susceptible to viral illnesses including respiratory conditions like colds, flu, and the novel coronavirus infection. Stress leads to the release of histamine, a molecule involved in allergies. In order to manage our stress mindfulness techniques need to be practiced everyday even if it is just for 10 minutes. Try things such as yoga, meditation, breath work, stretching or if you are having trouble switching off download an app on your phone that can take you thru a guided meditation.

4. Sleep

We all feel the benefits of a good nights sleep we wake up feeling refreshed and ready to take on the world. Whilst more sleep won’t necessarily stop you from getting sick, skimping on it could adversely affect your immune system, leaving you susceptible to a bad cold or case of the flu.
Without sufficient sleep, your body makes fewer cytokines, a type of protein that targets infection and inflammation, effectively creating an immune response. According to ‘The Sleep’,
“Cytokines are both produced and released during sleep, causing a double whammy if you skimp on shut-eye. Chronic sleep loss even makes the flu vaccine less effective by reducing your bodies ability to respond’.
To stay healthy during the influenza season get the recommended 7-8 hours of sleep per night. This will help keep your immune system operating at it’s optimum and also protect you from other health issues such as heart disease, diabetes and obesity.

5. Personal Hygiene

It goes without saying that practicing good personal hygiene is one of the most effective ways to protect ourselves and others against nasty viruses and bacteria. Ensure you wash your hands before and after preparing food and going to the toilet. Sanitise your hands after going to public places or gyms and cook meat thoroughly before eating.

Look After Your Gut

There has been some exciting research in recent years around the link between our gut bacteria and our health.  There is more and more scientific research coming out everyday to suggest that your gut bacteria (or microbiota) and the health of your gut lining affect your mind, mood and body in ways from minor (skin and energy) to major (chronic inflammation and disease).  Early life circumstances such as the method in which we were born either vaginally or by C section can further affect the way these microbes develop as well as whether any medications were prescribed to the infant or the mother during this early time.  It also appears that modern life and the way we live, where we are living, what we are eating and even things like how much stress we are under are having a huge impact on our microbiota balance (good bacteria vs bad bacteria).  The good news is, the more we understand about the importance of keeping our guts healthy the more we can influence these factors to improve our health.


How we are born affects our Gut:

When we are born the makeup of our gut microbes are determined largely by whether we were born vaginally or by C section.  A babies gut microbes from a vaginal birth are made up of skin, vaginal and faecal bacteria whereas babies delivered via C section are largely made up of skin only.  Acquiring the right combination of these microbes at birth have a major impact on the developing health of the baby, these microbes that we are acquire or do not acquire can affect the likelihood of developing diabetes, obesity and some cancers.  As more and more research are released about this topic, the latest findings tell us that gut microbe composition is associated with weight, cardio vascular disease and diabetes.  In fact, the same studies have shown that babies who are born via C section or who have been exposed to heavy loads of medications are more likely to be obese or overweight by up to 50%.  The science into this topic is so advanced that researchers can predict with up to 90% accuracy whether a baby will be lean or obese just by testing the microbes in your gut.


The good news is, if these microbes are missing or lost for any reason the baby can acquire them later in life thru breast feeding or specially designed pro-biotics which replicate the HMO structures found in breastmilk.


How where we live affects our gut:

According to Dr Rob Knight (Director of the Centre for Microbiome Innovation) we have over 100 trillion microbes living inside of our gut.  To give you a better understanding of what this looks like, imagine if you took a blade of grass and planted it for every microbe living in your gut, there would be enough of these blades of grass to fill 1 million football fields.


The purpose of these microbes have several functions they help us to:


  • Digest our food
  • Help educate our immune system
  • Help us resist disease
  • May even be affecting our behaviour


Interestingly, as our bodies adapt to life in a modern society we are losing some of our normal microbes.  In conjunction with this loss of microbes there are quite a few diseases that are skyrocketing in developing nations around the world.  We are seeing a prevalence for higher rates of obesity, diabetes, Crohn’s disease, ulcerative colitis, allergies and asthma.

Every one of these diseases and many others related to metabolism and weight and auto-immunity are linked to a loss of healthy diversity in the gut.


According to Rob Knight immigrants that arrive from South America and move to the U.S lose 20% of their gut micro diversity within a short time of moving there.  This loss of diversity is largely due to humans spending 90% of their time indoors and a decrease in the variety of plant based foods we are consuming.


Why? We are breathing in air from artificial and mechanical ventilation systems which have a completely different ecosystem from those you find outdoors.  Our outdoor counterparts have a greater and differing range of micro-organisms where this bacteria can colonise.


How what we eat affects our gut:


The food we eat plays an essential role in maintaining the diversity and proper functioning of our gut microbiota.  When talking about gut microbiota it could be said ‘we are what we eat’ as what we consume feeds off the trillions of bacteria living in our digestive system.  The bad bacteria in out gut thrives on processed foods, sugars, alcohol and other genetically modified foods.  Our good bacteria thrives on a balanced diet of vegetables, fruits, dairy and protein.


Interestingly, a study by Angela Genoni (Edith Cowan University, Australia) found that following a Paleo diet for more than a year is associated with unfavourable changes in gut microbiota composition and increased levels of a compound (trimethylamine N-oxide) an organic compound involved in the development of cardiovascular disease.  This was compared to individuals who followed a balanced diet that included grains, legumes and dairy which promoted the healthy balance of these healthy bacteria.


Probiotics vs Prebiotics:

Probiotics sometimes or ‘good gut bacteria’ are micro-organisms found in the human digestive tract that improve the balance of healthy bacteria.  Including probiotics and probiotic rich foods in our diets have shown to help reduce digestive symptoms such as constipation and bloating, restore gut flora after taking a course of antibiotics, after a bout of diarrhoea, during times of stress and when travelling where food and water borne illness is a possibility.  Try including these probiotic fermented foods in your diet where possible, yoghurts, fermented drinks such as kombucha and kefir, miso and fermented vegetables like sauerkraut and kimchi.



Prebiotics or sometimes referred to as ‘fermentable fibre’ are a type of fibre that feed probiotics.  They promote the growth and function of different types of good bacteria in the gut.  Prebiotics are naturally found in vegetables such as garlic and onions, leeks, asparagus, artichokes, tomatoes, bananas, plums, apples and in grains and cereals such as bran and in nuts like almonds.  For this reason, vegetables, fruits and cereals should be part of a balanced and healthy diet.


How what we eat affects our Mental Health:


The gut has often been referred to as the ‘second brain’ due to it’s production of serotonin (happy hormone) which assists in regulating our bowel movements.  This is separate from the serotonin production which occurs in our brains which is believed to regulate mood and social behaviour.


Researchers from the Catholic University in Leuven, in Belgium have found ‘most human gut bacteria do produce neurotransmitters, which are chemicals like dopamine and serotonin that enable communication among neurons, which are the nervous cells in the brain, but also in the enteric nervous system of the gut’.  These neurotransmitters are known to influence intestinal functions, but also our mood and behaviour.


Further into this topic Flemish researchers found from the Flemish Gut Flora Project (FGFP) discovered that two genus of bacteria were consistently depleted in the gut microbiota of people who were diagnosed with depression.  Whether they were following an anti- depressant treatment did not have any effect on the results.  It is important to note that from these studies although they have seen there are two bacteria lacking in the microbiota of people with depression it does not mean that these bacteria cause depression.  More studies need to be done to assess causality of this topic.



Stress also plays a significant role in altering gut bacteria.  Stress causes a decrease in beneficial bacteria and an increase in potentially disease-causing microorganisms.   It can also cause inflammation, bloating and make stomach ulcers worse.  It’s important to have some stress relieving measures at hand if you suffer from serious amounts of stress.


In finality, a balanced and varied diet is the key to optimal gut health combined with psychological and physical ways to manage stress.  Most disease and ill health is caused from poor gut health so it is really lends some weight to the saying “your only  as healthy as your gut’.


Kristy Curtis

Holistic and Lifestyle Coach and PT

Instagram: Kristy Curtis Health