While we know that a healthy diet is
important to keep your immune system working at its best, there are claims out there suggesting that a specific food, diet, supplement, or herbal product will “boost” your immune system. When considering such claims, it is important to first understand
the complexity of the immune system. Your chance of getting sick is influenced by diet plus other lifestyle factors. These include physical activity and rest in combination with factors such as age, body composition,
overall health status, innate immunity (your body’s natural defense strategy), adaptive
immunity (your body’s immunological memory resulting from past infections and vaccinations) and stress. Notice that some of these factors are within your ability to influence, while others are not. In truth, you can’t fully control whether you catch viruses such as COVID-19, nor can you fully influence how severe your body’s response will be if you do contract it.
This doesn’t mean, however, that your food choices are not important during this time. Although diet is just one of several factors that impact your body’s immune system,
it is one of the factors that you can improve. In addition, the benefits of eating well extend
beyond increasing immunity during this time
of COVID-19, including improved mental health and helping you to feel more in control
in a time when so much is out of our control.
So what foods and nutrients are important for a healthy immune system? Considering that your grocery budget may be limited,
here are some tips to consider when planning
your quarantine meals and snacks.
1. Eat a variety of colourful vegetables and fruits each day, which provide a host of
nutrients including vitamin C, which is known to aid your body in preventing and fighting infections.
Note that canned and frozen vegetables and fruits provide a cheaper alternative to fresh, and can be just as nutritious. Consider reaching for a bowl of frozen fruit (thawed, of course) to satisfy your sweet tooth. There are several fun varieties available, so you can have a taste of the tropics (pineapple, peaches, mango, etc.) even if your beach
vacation was cancelled this year. Top with
vanilla yogurt for an extra satisfying twist.
2. Be sure to include whole grains in your diet, including whole grain bread and pasta, brown rice, whole oats, barley, and quinoa. These foods are a source of zinc, which supports T-cells that are key players in the body’s immune response.
If you have been filling your free time by baking and cooking, now may be a great time to consider swapping out some (or even all) of the white flour in your recipes for whole wheat. This swap can be made in most recipes, including breads, quick breads, muffins,
pancakes, waffles, crepes, cookies, scones, and biscuits.
3. Focus on including protein-rich food sources with each meal. Protein foods include animal sources such as meat, chicken, eggs, and fish in addition to plant-based sources such as nuts, seeds, and legumes (beans, peas, lentils, and
chickpeas). Your body needs protein to produce antibodies, which are protective proteins within your immune system.
Using more legumes in your cooking (and even baking) may help you get the best value, in terms of both money and nutrition. As a starting point, try
adding ½ cup rinsed red lentils to every ½ kg ground beef, chicken, or pork that you cook - it is unlikely that you will even notice the difference!
4. Don’t be afraid of fat, but keep your focus on plant-based sources, particularly those that contain omega-3 fatty acids. Omega-3s help to keep your white blood cells (another type of cell within your immune system) functioning well. Walnuts, flaxseeds, chia seeds and oily fish are great sources of omega-3 fatty acids.
Consider canned salmon as a budget-
friendly way to eat oily fish (see recipe far right). You can also add ground
flaxseed to your breakfast oatmeal, cereal, or yogurt daily for an easy way to get your omega-3s.
Some people ask if nutrition supplements are beneficial during this time. This question
may require a more detailed individual assessment by a health care provider such as your physician or a Registered Dietitian.
However, note that vitamin D is an important
nutrient that has been shown to lower the odds of developing virus-induced respiratory
tract infections. Since most Canadians do not get enough vitamin D through food sources alone, a standard vitamin D supplement is recommended for most individuals.
You may have noted that the foods and
nutrients mentioned above are not so-called
superfoods or specialty items that will break the bank. Eating to support a healthy immune system simply involves eating a variety of whole foods which have benefits that extend well beyond immunity during this time of COVID-19.
In the far right column is a budget-friendly recipe based on pantry staples you likely have at home.
References:
https://www.precisionnutrition.com/optimize-your-immunity-infographic?fbclid=IwAR28oiyhgaGkSK-FWdURXdk0Cr2JYd69ZJGrPm-TTqFKEsaPR-5uLP8fEJ4
http://www.nutritionrx.ca/coronavirus-immunity/?fbclid=IwAR05rKX1CRhRQBSf0bKOE-35P7E1fMpH1q1bRXY2oC2FpgUKlij9JoRWiuY
https://www.hsph.harvard.edu/nutritionsource/2020/04/01/ask-the-expert-the-role-of-diet-and-nutritional-supplements-during-covid-19/?fbclid=IwAR0VJNf-l9BB53qihChmkInbk3X_LElvM-NEqU3MuWLvxCJDENWMP722-lA
Easy Stovetop Salmon Patties