Essential nutrients to nourish your immune system

As the cold and flu season draws closer, you may be wondering about ways to stay healthy and lower your chances of getting sick. Lifestyle habits like eating a balanced and healthy diet, and getting plenty of rest play an important part in keeping your immune system working at its best. Read on to discover some of the many essential nutrients that can provide a boost for you this season.

Vitamin A: You can find vitamin A in a variety of animal products, such as dairy products, and its precursor form, beta-carotene, in plant sources like dark, leafy greens and vegetables.1 Vitamin A plays a role in maintaining healthy skin and mucous membranes, as well as supporting our immune system health.1 It’s important to note that vitamin A levels can build up in your body, so ask your pharmacist if you’re unsure whether a supplement would be appropriate for you.1

Vitamin B: The B vitamin family encompasses 8 types of B vitamins, ranging from vitamins B1 through B12. Vitamin B6 for instance is theorized to help keep the immune system strong.2 Folate (vitamin B9) is needed to make new blood cells, which is vital during pregnancy to prevent birth defects as the baby grows.3 Eating a balanced diet, including animal or dairy products that are rich in vitamin B12,1 can help to prevent deficiencies. You’re more likely to be deficient in vitamin B6 if your other B vitamin levels, especially vitamin B12 and folate, are low.4

Vitamin C: Antioxidants, including vitamin C, are molecules that fight off harmful free radicals that damage our tissues and DNA.1 It’s also used by the body for wound healing and to maintain important structures such as our bones, teeth and gums.1,4 Vitamin C improves our ability to absorb iron, which is needed to produce new red blood cells.1 You can increase your vitamin C intake by consuming more fruits and vegetables, especially citrus fruits and vegetables from the cabbage family.1

Vitamin D: Although vitamin D is only found naturally in fatty fish and egg yolks, certain products like orange juice and milk may be fortified with it.5 Getting sufficient vitamin D enables us to absorb calcium more effectively, which helps to build strong and healthy bones.1,4 A link between vitamin D levels and your risk of immune system conditions and infections remains inconclusive but continues to be a hot topic for researchers.4 Keep in mind that vitamin D levels can accumulate in the body, similar to vitamin A. Ask your pharmacist to help determine whether taking a vitamin D supplement is right for you.1

Vitamin E: Vitamin E can be found in fruits, vegetables, nuts, seeds and plant-based oils.1 Much like vitamin C, its antioxidant properties help to protect your cells from harmful substances.1 High vitamin E intake can lead to build up within the body or increase your risk of bleeding. Ask your pharmacist first if you’re feeling unsure about taking a supplement, especially if you’re on blood-thinning medications.4

Selenium: This mineral is found in soil, which is then absorbed by plants and the animals that consume them.4 As a result, a variety of foods including poultry, red meats and grain products are good sources of selenium.4 It is used to maintain the function of certain enzymes in your body, which may help to protect against cellular damage and infections.4 Be careful not to take too much selenium regularly, as it can lead to health problems such as muscle tremors and brittle or discoloured nails.4

Zinc: Zinc is an essential mineral that is found primarily in meats, poultry and seafood.4 It’s thought that it can help to support the growth and function of immune system cells to fight off viruses and bacteria.4 You can often find it in over-the-counter products for the treatment and prevention of colds.4 It may also improve wound healing through its anti-inflammatory effects and role in creating new tissues and cells.4

Probiotics: Unlike other nutrients, probiotics are live bacteria and yeasts that can be taken to benefit your gut and overall health.6 They may be involved in regulating your immune system responses and fighting off harmful bacteria in your body.6 Probiotics can improve the symptoms of certain digestive disorders, and can increase your absorption of certain vitamins and minerals.6 Many fermented foods such as yogurts, sauerkraut and kimchi are natural sources of probiotics.6

Preparing for the cold and flu season involves more than bundling up for the cold weather outside. It’s a good opportunity to think about how you can better prepare your immune system to fight off infections. Speak to your Shoppers Drug Mart® pharmacist to see whether you would benefit from any vitamins, minerals or other supplements to keep your body functioning at its best.


  1. Vitamins: Their Functions and Sources (2020). HealthLink BC. Retrieved from: . Accessed July 20, 2021.
  2. Benefits and uses of B-complex vitamins (2019). Medical News Today. Retrieved from: . Accessed July 21, 2021.
  3. Pregnancy and Nutrition: Folate and Preventing Neural Tube Defects (2020). HealthLink BC. Retrieved from: . Accessed July 20, 2021.
  4. The Nutrition Source. Harvard T.H. Chan School of Public Health (n.d.). Retrieved from: . Accessed July 20, 2021.
  5. Vitamin D and Calcium: Updated Dietary Reference Intakes (2020). Government of Canada. Retrieved from: . Accessed July 20, 2021.
  6. Prebiotics and Probiotics (2019). GI Society Canadian Society of Intestinal Research. Retrieved from: . Accessed July 20, 2021.