Can certain foods help “boost your immunity”?

We've all been there – struck down by the flu in winter and rushing our family members to the supermarket to grab any and every "immune-boosting" food or supplement that they can fit in their basket. And as you start to wonder what's worse - the total on the supermarket receipt or your throbbing head - you wouldn't be foolish for wondering if there isn't a better (and cheaper) way to support your immune system.

Well, as it turns out, there's not a lot of conclusive evidence demonstrating that eating any one particular food, supplement or food group is wholly effective in supporting your immune system.

Instead, let's explore how the immune system works and why a healthy diet (and general healthy lifestyle) could be a far more promising form of protection against infection.

What does the immune system do?

Simply put, our immune system is our body's defence against infection. As the name suggests, our immune system involves several parts of the body working collectively to protect our body (including cells, tissues, and different organs).

When foreign microbes enter our body, our immune system works to recognise them as intruders and get rid of them. Our immune system can also 'remember' previous attacks so when it encounters an invader again our immune system can fight it off effectively and, typically, we won't get sick from it again – this is why vaccinations are effective.

In the absence of complications our immune system does a great job of protecting us. However, there a few conditions or circumstances that could put additional stress on our bodies and potentially impact the strength of our immune system; this includes:

• Conditions such as cardiovascular disease, diabetes, lung disease
• Psychological stress
• Other infections (i.e. influenza)
• Malnutrition

Without a doubt, our immune system is hugely important in staying well, and we should all be doing the best we can to keep it in top-notch condition.

What role does food play?

Our immune system is complex, and there is still a lot of research to be done on the impact of diet on immune function. That being said, we do know that eating a variety of foods from the five core food groups helps to ensure we are getting a variety of micronutrients (vitamins and minerals) and, dietary fibre, while also ensuring your diet is lower in saturated fat, salt, sugar.  

Consistently feeding your body a balanced and varied diet can assist in providing the best environment for our immune system to function effectively. 

Not sure where to start?

Here are some simple tips to help prime your body to fight infection:

• Eat colourfully – if your diet's colour palette is consistently monotone then, it's likely you're not getting a variety of vitamins and minerals from your food; different vitamins and minerals are helpful for different parts of our immune system.
• Choose whole (unprocessed or minimally processed) foods more often – heavily processed foods tend to be higher in salt and sugar and lower in essential vitamins and minerals.
• Adequately hydrate – aim to choose water as your main drink and keep a reusable water bottle with you to drink from throughout the day.
• Vary your protein choice – there are a lot of foods you can source protein from so it's always a bonus to get a variety of different sources like meat or plant-based proteins, such as tofu, beans, legumes, and nuts.
• Eat more vegetables – Not to sound like a broken record but seriously, eat more vegetables. Revisit the guidelines to understand how many servings you should be getting (typically five serves; one serve to be 1 cup raw or ½ cooked vegetables). Aim to have vegetables with two (or more) of your meals per day.
• Ensure you are eating within your energy requirements to help manage your weight – not sure what your energy requirements are? Check out this calculator.
• Choose food sources rich in vitamins and minerals. Supplements are not routinely recommended for the general population - for most people, it is best to get the required vitamins and minerals from whole foods.

In the short term, your diet actually might only play a small role in maintaining an effective immune system. Still, in the long run, the effects of a well-balanced, healthy diet, paired with a generally healthy lifestyle, will help to keep your body functioning optimally providing the best opportunity for a robust immune system as you age.