Food and Our Immune System

Food is essential to life. It is key for supporting our immune system and gives us energy for the activities we do every day.  Our immune system fights infections but it’s complex and influenced by many things, not just diet. Eating a variety of healthy foods along with keeping active, reducing tobacco and alcohol use, managing stress and adequate sleep gets the body ready to fight infection.

Is there an Immune-Boosting Diet?

People often look for special foods or vitamin pills to help fight infection. However, no single food can provide all the nutrition that your body needs to keep healthy. Each part of the immune system depends on many nutrients to respond to an infection. For example, Vitamin C, Vitamin D, folic acid, proteins, iron are just a few of the nutrients needed for the growth and maintenance of immune cells. These are found in a variety of plant and animal foods.

There is no special diet that can boost the immune system but following Canada’s Food Guide provides our best defense. Eating vegetables, fruits, legumes and wholegrains and saying “no” to processed foods, sweets and sugary beverages can result in better immune activity.

Will taking vitamins make my immune system stronger?

Immunity is often impaired in older adults, people with obesity and those who have higher nutrient needs. Older adults are especially at risk. With poorer appetite, budget limits, and lack of interest in cooking, older adults tend to less well nourished. Also, the immune system generally does not work as well with increasing age. In these cases, a vitamin-mineral pill (supplement) may be used as directed by a doctor, nurse practitioner or recommended by a registered dietitian. Be aware that vitamin-mineral pills are not substitutes for healthy food choices.

Vitamin D has been in the news as possible protection against severe outcomes of Covid-19 infection. While the science community is still studying the effects of Vitamin D on immunity, Health Canada recommends that adults take 600 international units (IU) up to age 70, and 800 IU after age 70. Most people cannot get enough Vitamin D from food or the sun.

7 Nutrition Tips to Support a Healthy Immune System

• Eat more wholegrains, colourful vegetables and fruits, and legumes like lentils and beans.
• Eat traditional and locally grown/harvested foods.
• Choose lean meats, fish, poultry. Leave processed foods like hot dogs, bacon, canned lunch meat in the store.
• Plan meals and cook more often rather than eating out or buying ready-made foods. You will have nutrient rich foods ready to go.
• Drink plenty of water. Add bits of fresh or frozen fruit or vegetables to flavour water.
• Make bone broth or chicken soup with vegetables for hydration.
• People with obesity may consider a modest weight loss to improve immune function.