Nutritionist Mags Carey gives her expert advice on how to boost your immune system and fight a cold. Plus she shares her recipe for a flu-fighting hot toddy!

The old adage of 'prevention is better than cure' definitely applies here – so how can we make sure our immune system is functioning as well as possible? These top tips will help get you through the changing seasons, without having to rely on expensive supplements that we often forget to take!

1. Avoid immune system suppressants
Everyone knows that too much sugar, caffeine, alcohol, and processed foods are bad for you, but did you know that they could actually compromise the function of your immune system? It's best to limit them in your diet to make sure you don’t tax your body any more than you should, leaving you feeling run down.

2. Eat a rainbow!
This basically means to eat as wide a variety of coloured fruits and vegetables as possible – this ensures that you’re getting a range of antioxidants that we know can help in the prevention of bugs.

Healthy Food Platter

3. Get enough sleep
Insufficient sleep is thought to disrupt our circadian rhythm, which in turn impacts effective immune response. Getting our eight hours' sleep has never been more important!

4. Take regular exercise
Studies have shown that people who exercise moderately (even a brisk walk) for 30 minutes every day have half the number of colds than those who do no exercise. But before you start running marathons, it’s worth bearing in mind that too much exercise can actually stress your immune system and reduce its ability to function optimally.

5. Keep it clean!
There has been lots of talk in the media about us being "too clean" and the link with auto-immune conditions, but good hygiene is imperative in order to avoid the spread of germs.

Particular care should be taken when preparing and eating food, after using the bathroom and after sneezing or coming into contact with someone who is ill or in hospital.

6. Manage stress
Chronic, long-term stress can result in a myriad of problems, brought on by exposure to stress hormones, predominantly cortisol. This can also result in lowered immunity.

While the complete avoidance of stress is impossible in this day and age, taking necessary steps to combat the effects of stress such as taking up yoga, meditation, walking etc. can go a long way to improving our overall health.

manage stress

7. Support your gut
Did you know that 80% of your immunity is located in your gut? It is so important to have a healthy, functioning gut and adopting a healthy eating lifestyle with lots of fibre-rich foods such as lentils, beans and vegetables can help keep things ticking over.

Probiotic foods such as kefir, yoghurt and sauerkraut are excellent ways to increase our good bacteria and give our immune system a helping hand.

8. Stock up on immune boosting foods
Certain foods have been proven to naturally boost our immune function, including garlic, herbs (especially mint, thyme, ginger and oregano), mushrooms (specifically reishi and shiitake), honey (go for a locally-sourced one) and teas (specifically green and matcha teas).

Sick woman with flu

If you get sick:

1. Rest
If your throat starts to feel tickly and you feel like something is brewing, use it as an excuse to take to the couch or bed and rest up. This will give your immune system the chance to direct its energy to where it needs to go. Far too often we fight through these warning signs and end up worse for wear in the long run.

2. Drink warm liquids
Staying hydrated is the key to limiting the side effects of colds and flus such as a stuffed nose and headaches.

3. Avoid mucus-producing foods 
A lot of people find that dairy foods can leave them feeling bunged up, so avoid foods you know will irritate you until your symptoms abate.

4. Take a hot shower or bath 
The moisture can help clear nasal passages, which can clear the head and lead to a better night's sleep – all of which is helpful in terms of recovery. Adding a few drops of essential oil to your bath or a burner, such as eucalyptus or lavender, can also help ease your symptoms.

5. Eat well 
While eating your body weight in oranges won’t necessarily prevent you from getting sick, there is sufficient evidence that vitamin C-rich foods can help reduce the duration of a cold. So while you may have lost your appetite and only feel like eating toast, adding lots of fresh fruit and vegetables to your diet will see you back on your feet much quicker. Homemade smoothies are a great, quick way to do this.

Two Mugs of Lemon Spice Herbal Tea or Hot Toddies

Flu-fighting hot toddy!

Ingredients (to make a pot)

  • Pot of warm water
  • 3-4 thin slices of fresh ginger root
  • 2-3 tblsp fresh lemon juice
  • 1 tblsp locally-sourced honey
  • Handful of fresh mint


  1. Add all of the ingredients to the pot of warm water and allow to infuse for several minutes.
  2. Your tea is ready to go, either straight from the pot or strained! Drink liberally throughout the day, adding some more warm water if needed.

Maggie Carey has a BSc in Applied Science from Trinity College and is a qualified nutritionist, herbalist and naturopath. As a busy mum of two young children, she fully understands the need for quick but nutritious meals to fuel families and fight off infections.

Nutrition Division, 29 Fitzwilliam St Upper, Dublin 2. T: 01-6629231. You can visit them online on or email