Boost your immune system and avoid colds and flu this winter
Boost your immune system and avoid colds and flu

There’s always plenty of talk at this time of year about boosting your immune system so you keep well and don’t succumb to coughs, colds, flu and other illnesses. But what exactly is your immune system and how can you ensure it’s in top working order, ready to protect you?

The immune system is a collection of cells and organs that protect our bodies from invaders such as viruses, bacteria, parasites and fungi that could harm us. It includes your white blood cells, bone marrow, tonsils, lymph nodes, spleen, the tiny hairs in your nose and your digestive tract.

Your white blood cells recognise the cells that make up your body and will attack any unfamiliar cells. When our immune system does not succeed in fighting off these microorganisms, that’s when we suffer from infection and illness.

So it is ideal to strengthen our immune system by following these guidelines:

Healthy diet


Sugar is the number one food to avoid. It decreases the function of your immune system almost immediately and has been shown to affect your white blood cells’ ability to kill bacteria. Remember that sugar is present in foods you may not suspect such as fruit juices and ketchup.


Scientists have found that being overweight or obese leads to a weakened immune system. This is thought to be because excessive weight harms the ability of white blood cells to produce antibodies and multiply in order to fight infection.

Processed food

Avoid highly processed foods that often contain chemical additives, pesticides and preservatives which can also weaken your immune system.


Instead, be sure to consume plenty of foods that are rich in nutrients. These should include a wide range of fruit – especially berries – and vegetables, whole grains, meat from grass-fed animals, organic eggs, coconut oil, nuts, seeds, fermented foods, herbs and spices.

Antioxidants and free radicals

Berries are just one source of antioxidants which fight free radicals in your body. Free radicals are unstable molecules that lack electrons. They form naturally as a result of normal metabolic processes but they can increase due to a poor diet as well as from stress and environmental factors. As we get older, we might notice that our immune system is not working as well as it used to – that’s because it is being damaged by free radicals.

Your body does produce antioxidants itself to neutralize free radicals. But as we age, the levels of antioxidants drop significantly. So boost your immune system by eating plenty of foods rich in antioxidants such as vitamin C, vitamin E, carotenoids and bioflavonoids. Here are a few examples of what foods can supply you with these:

Vitamin C
Kiwi, oranges, tomatoes, broccoli, peppers, strawberries.

Vitamin E
Nuts, seeds, whole grains, leafy greens, olive oil.

Carrots, mango, peaches, apricots, broccoli, spinach, kale, squashes.

Peppers, strawberries, citrus fruit, garlic, spinach, green tea, garlic, mango, papaya, beans, chickpeas, onions.

Cut down on alcohol

Alcohol affects the immune system in two ways. Firstly, it produces an overall nutritional deficiency and secondly it hinders the white blood cells’ ability to break down and destroy invading microorganisms. This means heavy drinkers are more vulnerable to infection.


Be sure to get enough sleep. If you don’t get sufficient, uninterrupted sleep, it has a negative effect on your immune system and you will not be able to fight off potential invaders. Studies have shown that people who do not get enough sleep are more likely to succumb to viruses if they are exposed to, for example, a common cold virus.

A lack of sleep can also affect how quickly you recover if you do get ill. In addition, not getting enough sleep is also linked to an increased chance of other serious health issues such as heart disease, stroke, diabetes and hypertension.

Most adults need between seven and eight hours of sleep each night. Teenagers usually need about nine or ten, while children should have at least 10.


When people are continually stressed, their adrenal glands release more cortisol, draining the body of vital energy. Elevated cortisol levels cause certain immune system cells in our blood to disappear, thereby weakening the immune system.

We know that many people experience stress regularly. So it is wise to manage stress levels effectively, using the ways that work for you. Prioritise things that help you relax. Consider taking up yoga or tai chi, meditation, breathing exercises, enjoy a walk in the countryside, take a relaxing bath, spend time with family or friends; whatever you find rejuvenates you.

Wash your hands

Washing your hands frequently can help you stay healthy. When you have touched something contaminated with a virus or bacteria, you can then spread it to your own mouth, nose or eyes, and to other people. Clearly, if wash your hands, you decrease the chance of spreading a virus or bacteria. Of course, if your immune system is strong, it can fight off a virus that does enter the body but washing hands will decrease the pathogens that make it into your body in the first place.

There is absolutely no need to use anti-bacterial handwash. Using it increases the risk of creating resistant bacteria, and anti-bacterial handwash also contains lots of toxins. Good old-fashioned soap and water works very well. To ensure you wash your hands thoroughly, if you sing the Happy Birthday song twice through, you have washed for long enough!


Exercising increases the blood circulating around your body and this means those essential white blood cells are being carried around more quickly. This gives your body a better chance of finding an invasive pathogen before viruses and diseases have a chance to take effect.

Be sure to not over-exercise as, while moderate exercise is a good thing, over doing it can cause a physical strain on your body. So give your body sufficient time to rest and recover. If you are not used to exercise, be sure to start slowly, perhaps with something gentle like regular walking.


Water is absolutely vital to virtually every function in the body, including all the work your immune system does. Water can flush out toxins so ensure you drink plenty.

Now that you are aware of some of the factors that can weaken your immune system, you can avoid them and change some lifestyle habits to help keep your immune system strong.