Understanding Your Immune System

Understanding Your Immune System

Harriet Walker; Accredited Practicing Dietitian and Accredited Sports Dietitian. A leader in the sports nutrition space within Australia, specialising in strength sports.

What is the immune system?

Our immune system is an overarching term for a number of different systems within our body that keep us safe from invaders such as bacteria, viruses, and chemicals. Our immune system is made up of organs, specific tissues, cells, and molecules, all of which act together at various stages to kill off any potentially life-threatening pathogens that enter our body.

There are two arms to our immune system, the Innate immune system, and the Adaptive immune system. The Innate immune system is non-specific which is targeting and very quick to respond once it identifies a threat, however, it does not remember if it sees the same invader more than once. It will respond the same way each time. Our Adaptative immune system is more considered and specific in its response to a pathogen, however, this means it takes longer to respond, yet next time it sees the same pathogen, it goes through the process much faster.

Inflammation, vital responses to unwanted particles in our body such as bacteria and viruses, does, however, deplete our body and more generally, when we do not eat well over a long period of time, low intakes of nutrients that support the immune system can leave our immune function compromised.


How can nutrition influence our immune function?

The foods we eat on a regular basis provide us with nutrients- macronutrients (carbohydrates, fats, and protein) and micronutrients (vitamins, minerals fibre) as well as health-enhancing antioxidants and phytochemicals all of which contribute to our health long term and short term.

From a macronutrient perspective, each one plays a role in keeping our body healthy. Carbohydrates provide glucose for our cells and can help reduce the stress response, particularly after large bouts of exercise. Healthy fats are not only a source of energy but provide essential fatty acids which are anti-inflammatory. And protein is involved with many processes including cell development. A balanced diet includes each of these macronutrients, however actual split across the three will differ from person to person.

When it comes to plants, they provide us with a wealth of compounds that have anti-inflammatory antimicrobial. Herbs, spices, and teas such as green tea, cinnamon, garlic, ginger, and turmeric are well documented to protect our body from illness and heart health-promoting compounds like nitrates found in vegetables including beetroot, pomegranate, and dark green leafy vegetables also play a role in keeping the body healthy.

The benefits come from eating a variety of them of fruits and vegetables and eating them often. As people commonly say, one salad doesn’t make you healthy, and one burger doesn’t make you unwell. Our body requires regular doses of vitamins and minerals and antioxidants to keep our health on track across the lifespan.

Different colours of fruits and vegetables will provide us with different types of beneficial phytonutrients. This means that by having a variety of colourful fruits and vegetables in your diet daily helps to expose your body to a wide variety of health-boosting compounds without you having to get too specific. Here are some tips to help you boost the fruit and vegetable variety in your day.

Start your meal by filling half your plate with vegetables

Aim for three different colours each meal

Try to rotate your fruits and vegetables with the season- it’s cheaper to eat seasonally and foods that are in season are going to have higher nutrient content.

Use herbs and spices to flavour your food to boost the nutritional value minus the calories.


Gut Health

The gut is one of the lines of defence for our immune system. It provides a physical barrier against ingested pathogens, plus it houses trillions of bacteria which also work with us to fight unwanted particles that have entered our body.

By consuming adequate fibre, brightly coloured fruits, and vegetables, drinking plenty of water, and reducing our alcohol intake, we can help keep our gut healthy.

Probiotics can also play a role in keeping the gut healthy. Both probiotics foods and supplements can help when the balance of the gut is out by reintroducing beneficial bacteria to repopulate the gut and help re-establish balance and repairing damage to the gut lining.

Pantry Essentials for a healthy immune system.

Firstly, it is important to remember that much of the benefit of healthy eating comes when we follow a healthy pattern of eating over the long term. Shorts sprints of healthy eating may not have as big an impact as longer-term patterns.

However, if you want to review your current patterns, and start on some new patterns. Now is a good time.

Build your healthy pantry and fridge

Frozen and tinned alternatives are still great

When fresh produce is short supply, don’t be afraid to look at the frozen and tinned option. Tinned tomatoes can be the base of many great recipes, legumes are a great source of plant-based protein and fibre and frozen vegetables are easy to keep on hand to throw into slow-cooked meals, stir-fries or even to throw into smoothies.

Seek wholemeal and wholegrain options

Choose wholemeal or wholegrain dry ingredients when stocking the pantry to ensure your fibre intake is on track. Items such as brown rice, oats, wholemeal pasta, quinoa, and flours are useful to have on hand for main meals and baking.

Spice it up

Build up your herbs and spice collection to make sure you always have delicious and healthy flavours on hand. You can also puree fresh herbs and freeze them in ice cubes to use later.

Stock up on omega 3 fatty acids

Tinned and frozen fish can be easy sources of omega 3 fatty acids which help boost both immune function and protein intake.

Use legumes for satiety

Portion out meats to freeze and don’t be afraid to pad out meat-based recipes with legumes to boost the protein content and feel fuller for longer without having to add in more meats.

Always have a shelf life protein handy

Whey protein powder is a great shelf-stable source of protein that you can add to smoothies and baking to bump up the protein content of your snacks. It can also be used if freezing fresh vegetables, make sure to quickly blanch them first in boiling water to help avoid them becoming frostbitten in the freezer

Utilise your slow cooker

Slow cookers are fantastic for cooking bulk recipes and freezing them for later. They conveniently cut down your time spent in the kitchen. And it can be much cheaper to prepare your meals when using cheaper cuts.

It can be a pretty overwhelming listening to a lot of the information passing through social media right now. However, the best thing to do is to stay informed via credible sources, be prepared, but also know that if we all work together, then the situation will be a whole lot better than when we work just for ourselves.

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