Is your diet harming your immune system?


Emma Thornton
Qualified Nutritionist (BSc, MSc, RNutr)
@EmmaThornton
Ask Emma


25 April 2018

Can your diet affect your immune system?

As with every system in your body, your immune system relies on a delicate balance of vitamins, minerals and other nutrients to function optimally. If you’re not eating the right foods, it can affect a number of different functions within your body, such as sleep, digestion and stress, which can then have a knock-on effect on your immune system.

Research also appears to back up this idea of ‘you are what you eat.’ A recent study conducted by the University of Bonn in Germany found that, in the longer term, a Western diet can make your immune system hyper-responsive to inflammation triggers.1  

Inflammation, as I’ve discussed in some of my previous blogs, is an important part of your immune response, but when it becomes chronic it can spell disaster for your body as a whole! In this study, eating a typical Western diet was able to alter the gene expression in the subjects, although further human research is still needed to examine this effect more thoroughly.

What is a Western diet?

You may have heard me refer to what is known as a ‘Western’ diet before without really elaborating what this diet really consists of or where the diet originates from. A ‘Western diet’ is loosely based on the predominant foods consumed in the western hemisphere i.e. America, Canada and the UK. 

It generally has negative connotations as a typical Western diet mainly involves a higher intake of processed foods, refined sugars, salt and carbohydrates which can be associated with major health concerns such as hypertension, diabetes and obesity. When it comes to your immune system, certain food groups that are prevalent in the Western diet are thought to have a negative impact on your immune system. Below I’ve listed three of the most common culprits!

Red meat: Red meat is a good source of iron and other nutrients so most experts don’t see a problem with including this in your diet. However, moderation is key and unfortunately, many of us eat far too much red meat which can have unhappy consequences for our health, as elaborated in one recent study by the University of California. This research found that red meats such as beef, lamb and pork, contain a special sugar, Neu5Gc which is naturally produced by carnivores but not omnivores such as humans.2 When large amounts of red meat are consumed, your immune system may recognise this sugar as a pathogen and inspire an inflammatory immune response.

Fried foods: Unlike red meat, most of us are aware that fatty fried foods are not our friend. Not only are these types of food terrible for your cholesterol and capable of weakening your immune system by instigating an inflammatory reaction, one study found that reducing your intake of fatty, fried foods may help to restore your body’s natural defence mechanisms.3  This doesn’t mean that you have to completely eliminate fried chicken or chips – as an occasional treat, there’s nothing wrong with indulging in these types of foods but occasional is the operative word!

Refined sugars: Just like fried, fatty foods, refined sugar is an obvious health risk, but it may be even more prevalent in our society. Sugar isn’t just found in chocolate bars and boiled sweets – it can lurk in yoghurts, fruit juices and processed carbs such as white bread, pasta and rice. Although most guidelines recommend around 30g of sugar a day, you can find almost half of this in some fruit juices and nearly double in specialised lattes and hot chocolates! While this intake of sugar can exacerbate skin problems, upset your sleep patterns and interfere with your digestion, it can also affect your immune system by inhibiting the immune cells responsible for attacking bacteria!4 

The best nutrients for your immune system

In his blog, ‘3 essential vitamins and minerals for the immune system’, our Immune System Expert Dr Jen Tan goes into a bit of detail about the types of nutrients that can help to support your immune system – needless to say, vitamin C, zinc and vitamin D ranked pretty highly on the list! Fortunately, there are plenty of dietary sources of these important vitamins and minerals – just check out my favourite immune-boosting recipes below!

Kiwi & Ginger Green Smoothie

Kiwis’ are incredibly rich in vitamin C which can help to enhance your immune system by supporting your population of white blood cells, helping you to fight infections more efficiently. Ginger can also act as a natural anti-inflammatory so this is a great combo! 

Creamy Almond Butter Acai Bowl

Berries such as blackberries, blueberries  and acai berries are loaded with vitamin C so they’re another great way of upping your intake. This Creamy Almond Butter Acai Berry Bowl is also loaded with protein, fibre and healthy fats so it’s the perfect way to kick-start your day!

Pumpkin Spice Breakfast Bars

Pumpkin seeds are bursting with zinc, an important but often overlooked mineral that can help to regulate your immune function! These tasty bars are also rich in fibre thanks to the inclusion of flaxseeds and make for a delicious midday treat!

If you want more ideas about which foods to incorporate into your diet, please check out Dr Jen’s blog, ‘How can diet boost our immune system?

What about supplements?

If you are looking to boost your immune system, supplements may seem like an obvious answer. Not only do they contain concentrated amounts of certain nutrients, they’re a simpler alternative to completely modifying your diet. However, this approach isn’t always useful and studies have shown that supplementing can’t compete with actually increasing your dietary intake.

Your body is designed to absorb nutrients from your food which is why some supplements are not as well absorbed or utilised by your body. Although in certain instances, such as vitamin D, supplementing is sometimes recommended during the winter months, when sunlight is sparse. In general, you are always advised to increase your dietary intake first. 

However, if you are looking to support your immune system, you could try our Nature-C Tablets. Derived from the naturally occurring vitamin C found in fruit, this form of vitamin C is usually better absorbed by your body as it does not contain the same synthetic ingredients found in many other supplements! 

In instances when you feel a cold or flu virus manifesting it may be more useful to switch to our Echinaforce Echinacea Drops. These contain extracts of organically cultivated Echinacea, a herb traditionally associated with supporting your immune system and warding off the symptoms of a common cold or flu!

1https://www.medicalnewstoday.com/articles/320616.php

2http://www.pnas.org/content/112/2/542

3https://academic.oup.com/jcem/article/94/11/4483/2596935

4https://www.webmd.com/cold-and-flu/cold-guide/10-immune-system-busters-boosters#1

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