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Our immune system is our first line of defence against viruses, bacteria and exogenous toxins. But sometimes we need a helping hand to stay healthy! Naturally boosting your immune system means adopting healthy lifestyle habits and dietary practices that help strengthen your body’s natural immune response. Natural products, such as plants and herbs, essential oils, and vitamins support healthy lifestyles. They work together to strengthen your immune response and improve your overall health.

Vitamin C

Vitamin C is an essential nutrient that the human body cannot synthesize. It is found in abundance in fresh thyme and parsley, citrus, guava, bell peppers, kiwis and papaya, to name a few. Vitamin C stimulates white blood cells, which are responsible for protecting the body from infection. Taking vitamin C daily to try to prevent colds will not protect most people but can shorten the duration of a cold. Taking vitamin C when cold symptoms appear will have no effect. Vitamin C supplements are therefore commonly used as a preventative measure to strengthen the immune system, especially during cold and flu season.

Vitamin D

Vitamin D plays a key role in regulating the immune system. It is produced in the skin when exposed to the sun and is also found in foods such as fatty fish, mushrooms and egg yolks. Vitamin D stimulates the production of antimicrobial peptides, which help fight infections. In addition, it is also linked to a reduced risk of autoimmune diseases. In 2021, Health Canada increased the permitted daily over-the-counter supplement intake to 2,500 IU for people 9 years of age and older.


Zinc is an essential mineral that plays a crucial role in the immune system since it is required for white blood cell production and in regulating inflammatory response. Foods high in zinc include oysters, squash seeds, legumes and dairy products. Taking zinc within 24 hours of the onset of a cold has also been proven to reduce the duration of a cold in healthy people. On the other hand, you should not take zinc daily for more than three consecutive months to avoid disrupting your intake of other minerals.


Elderberry flowers, berries, and leaves are packed with antioxidants (flavonoids) and vitamins, making it an excellent plant for strengthening the immune system. Elderberry has antiviral and mucolytic properties that support the immune system when you experience sinus or chest congestion. Taken before and during the cold season, elderberry reduces the severity of winter ailments.

Essential oils

Some essential oils have properties that can benefit the immune system. Eucalyptus radiata is one of them, thanks to its high levels of terpenes, which have strong mucolytic, antibacterial and antiviral properties and specifically aid the respiratory system. It can be used in a diffuser, through steam inhalation, or as a topical rub diluted in vegetable oil.

Lemon essential oil has monoterpenes that are antibacterial and antiseptic. They can be used as a disinfectant when diffused in the air and add a mild, soothing scent to your home.

It is important to take precautions when using essential oils. Consult a naturopath if you have any questions or concerns.


Probiotics are beneficial bacteria that promote a healthy balance in your gut microbiota. Gut health is closely linked to a strong immune system, since roughly 70 per cent of immune cells are in the gut. Most probiotics contain bacteria belonging to the genus Lactobacillus or Bifidobacterium. Scientists distinguish them by subspecies and strains (e.g., Lactobacillus rhamnosus Lr-32). Even if two types of probiotics are from the same genus (Lactobacillus or Bifidobacterium), different strains offer different health benefits. This is why there are various probiotics with distinct strains that are better for the microbiota of men, women, pregnant women, children, older people, and people with intestinal, urinary or dermatological issues. Many people want to find the right dose for their health. No strict dose-response relationship has been proven in scientific studies. Again, depending on your age, gender, or the ailment you’re treating, dosages will vary. For example, a 10 billion CFU dose of probiotics is the threshold dose in reducing the risk of diarrhea associated with antibiotics. If you would like to add probiotics to your diet, ask for advice on which ones will work best for you.

To conclude, natural products such as elderberry, vitamins, essential oils, zinc and probiotics can play a significant role in supporting and strengthening the immune system. It is important to note that these natural products are not a miracle cure, but they can help strengthen the immune system when incorporated into a healthy lifestyle. Before taking dietary supplements, consult a naturopath to assess your individual needs.

Remember, a healthy diet, regular exercise and a healthy lifestyle are the best ways to boost your natural immune system!

Delphine Kubica, Naturopath and EESNQ graduate

École d’enseignement supérieur de naturopathie du Québec

The health and medical information published or presented in this article is the opinion of the author only and should not be used as a substitute for professional medical advice. Readers should use their judgment. It is their responsibility to independently verify the information provided in the article. The contents of this article are for discussion and informative purposes only and should never be used as a substitute for professional medical advice, diagnosis, or treatment. A medical professional is the only person who can evaluate your health and give you advice following a medical examination. Rachelle Béry will not be liable for any of the information presented in this article or in any associated links, nor the use or misuse of the information.

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