It’s important that our immune systems stay strong to fight off seasonal illnesses like flu and colds, as well as the COVID-19 virus. While we all need to continue to wear facial coverings in public spaces, maintain physical distancing, and wash hands frequently, we can also take steps to keep our immune systems strong to fight off illnesses. There is no magic pill that can strengthen the immune system overnight, but there are some steps we all can take.
A healthy diet, that is high in vegetables and fruit and low in added sugars and processed foods, can provide important vitamins and minerals that help our immune systems stay strong to fight infections and illness. Getting good quality sleep, finding ways to decrease stress, and getting regular physical activity can also keep us healthy.
All cells and organs in our body require vitamins and minerals from our diet to function properly. But for our immune system, the network of cells and proteins that defends our body against infection, vitamins C, D, E, and zinc are especially important.
We do not have evidence that taking vitamins C, D, E or zinc will prevent or cure COVID-19. But we do know that people with healthy immune systems who are physically active and maintain a healthy body weight, have less severe symptoms when they contract COVID-19 compared to people with conditions like high blood pressure, obesity, and diabetes. Poor health puts people at higher risk for hospitalization, ventilation, and death from COVID-19.
Building and maintaining a healthy immune system is a slow process, not a quick fix. Try to get a regular dose of these 4 immune-boosting vitamins and minerals from your diet:
An antioxidant that is stored by immune cells and then quickly used when we are actively fighting infection. Sources of vitamin C include: citrus fruits, strawberries, broccoli, and bell peppers. One large orange provides the recommended daily vitamin C dose for adults.
This vitamin is activated in our skin by UVB light from the sun. Immune cells use it to communicate with each other to launch an attack against infection. When the days get shorter and sunlight is less intense, we can get vitamin D from fatty fish (sardines and mackerel) or fortified milk or orange juice. A vitamin D supplement is a good idea in the winter if you don’t eat these foods. Look for a supplement that provides vitamin D3 at 600 – 1000 IU per day.
This is another antioxidant that protects immune cells. It prevents them from being damaged or losing their potency. Vitamin E is found in fatty plant foods like seeds, nuts, avocados, and vegetable oils. Adults can get the daily recommended amount by eating 2 ounces of almonds or sunflower seeds.
This mineral is critical for immune cells to develop and function normally. Too little zinc results in immune cells that cannot kill off bacteria or viruses effectively. Increasing food sources of zinc, or taking a zinc supplement, is especially important for adults over the age of 60 because our ability to absorb zinc declines as we age. Meat, shellfish and beans are good sources of zinc. A 6 ounce steak or 2 large oysters, would provide the recommended daily amount of zinc for the average adult.
Other non-dietary ways to support a healthy immune system:
- Get outside, take a walk
- Get regular mild to moderate exercise—30 to 45 minutes, five times a week.
- Find ways to reduce stress, such as hobbies, meditation, yoga, or deep breathing exercises
- Get plenty of sleep
- Don’t smoke
- Stay connected with loved ones via technology
- If you don’t eat a lot of fruits and vegetables or meat, take a daily multivitamin which includes Vitamins C, E, D3, and zinc, to help you get these important immune-boosting vitamins. Even if you get these vitamins from your diet and take a multivitamin, there is very little risk of getting too much. Talk with your healthcare provider before you start taking high-dose supplements of any kind.
People with certain medical conditions. Centers for Disease Control and Prevention. Updated October 16, 2020. https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html
Healthy Eating Tips. Centers for Disease Control and Prevention. Updated October 21, 2020. https://www.cdc.gov/nccdphp/dnpao/features/national-nutrition-month/index.html
How to Boost your Immune System. Harvard Health Publishing, Updated April 6, 2020. https://www.health.harvard.edu/staying-healthy/how-to-boost-your-immune-system