By Dan Rodgers, MD, family medicine physician at The Portland Clinic.
With the coronavirus sticking around and flu season approaching, maintaining a healthy immune system is more important than ever. People with a suppressed or lowered immune response are at high risk of severe illness, and even death, from COVID-19, influenza and pneumonia. Your immune system is your body’s line of defense against these and other threats, and right now, it’s vital to do everything you can to keep your defenses strong.
When your immune system detects a threat, such as a virus, it signals a vast network of cells, proteins and other players to mount a defense, or “immune response.” Nearby players leap into action to eliminate the threat, while others work to clear out damaged cells and to create antibodies that help build immunity to future threats. Naturally, the system works best when the rest of you is at its best — which is why some of the most important things you can do to support your immune system are good for the rest of you, too.
Fuel your immune system with nutritious food
People who are malnourished tend to have weaker immune systems. Mal-nutrition doesn’t just happen to people who eat too little — even people who eat a lot can be malnourished if they focus on fatty, sugary foods and skimp on foods that provide essential vitamins and minerals. Fuel your immune system by eating a balanced diet that includes a wide variety of fruits and vegetables (see our featured veggies on page 8), and work toward a healthy weight by avoiding high-calorie/low-nutrition foods. Don’t rely on “immune-boosting” supplements — most of these claims aren’t backed by research.
Keep your immune system on its toes
Research suggests that enjoying moderately intense physical activity on a regular basis enhances the immune system, as well as many other aspects of life and health. I recommend trying to get about 150 minutes of activity per week (that’s just 22 minutes a day). Do whatever you like, as long as it gets your heart thumping a little faster. Walking, bicycling, gardening and dancing all count.
Give it a good rest
There is strong evidence that a good night’s sleep promotes a better immune system. Research shows that early in the sleep cycle, we produce more T cells, which are white blood cells that specialize in boosting immune responses and promoting lasting immunity. Getting too little sleep, on the other hand, signals your adrenal glands to release cortisol, a hormone that can suppress immune function if it stays chronically high. Sleep is not a luxury. Make it a priority.
Do something to relieve stress
Cortisol is also known as the stress hormone, because your body releases it when you’re under stress (and also when your blood sugar is low). Meditating, practicing mindfulness and spending time in nature are healthy ways to reduce stress. Getting some sleep and physical activity also help. And while physical distancing is still important, staying socially connected to the people you love is critical to your mental health, which also is likely to reduce cortisol.
Quit tobacco, cut back on alcohol
If you smoke, quitting will improve your lung health and lower your risk of pneumonia. If you drink, keep it moderate; chronic overuse of alcohol can suppress your bone marrow, which is the factory that produces immune cells.
Take extra measures to stay safe — especially if you’re at high risk
Certain medications and conditions, including autoimmune diseases, diabetes, kidney disease, cancers and blood disorders, can weaken the immune system. If you’re concerned, talk to your provider about precautions you should take.
In general, all of the measures above will support your immune system’s ability to fight off viruses, but they’re not a replacement for physical distancing and wearing a mask. These remain crucial, not just to protect yourself, but also to protect those around you whose immune systems are weaker than yours.