Given that unfortunate reality, building up a personal defense system against an invisible enemy is paramount, according to the experts.
In March, Banner Health published a blog post: “How You Can Boost Your Immune System,” with the message: “A strong immune system is the ultimate defense against illness, whether it’s COVID-19, seasonal flu, or something else.” The post’s advice is largely mundane: Get eight hours of sleep, eat nutritious foods, exercise, hydrate, and do what you can to reduce stress in an incredibly stressful time.
Most people understand that adopting healthier habits is a good idea, but can these habits really boost your immune system so that a coronavirus infection looks more like, say, a common cold? Jessica Lancaster, an immunologist researcher at the Mayo Clinic, thinks it’s a distinct possibility.
“If you had two people with the same virus exposure and very similar genetic makeup,” Lancaster said, “and if one had been better overall — sleeping, eating well, and exercising — that person would most likely be much better off than the person who is not caring for themselves as well.”
The microscopic novel coronavirus typically enters the body through the nose, she said. From there, it begins a deliberate and dangerous process of multiplying and penetrating deeper down the respiratory tract and into the bloodstream. A spry immune system — bolstered by exercise, healthy food, and plenty of sleep — will harass the virus before it wreaks the kind of havoc that requires hospitalization, ICU admission, or a ventilator.
How the Immune System WorksEssentially, the immune system is a collection of cells, surveilling our body for unwelcome visitors: viruses, bacteria, various toxins, and cancer. When something isn’t right, alarm bells go off and the immune system springs into action to make things right.
In the case of COVID-19, the virus hijacks lung cells and eventually damages them to where they become inflamed. But when there is chronic inflammation in people, such as those with preexisting conditions like heart disease or lung disease, the immune cells are worn out or lulled to sleep.
In these cases, Lancaster said, “[immune cells] are kind of used to hearing these signals over and over again. When they have to actually respond to something, they're already exhausted.”
For example, if you are regularly exposed to toxic chemicals that cause inflammation, like cigarette smoke, you can have a “boy that cried wolf” situation, where the body gets jaded to these constant warning signs of trouble and is slower to respond.
For someone with COVID-19, any kind of delayed immune response can be catastrophic.
“When you have something that is quite aggressive like coronavirus, which can strike really quickly … if you have a lagging immune response, that can be devastating because by the time everything is mobilized, it’s too late. There's too much damage to the lungs,” Lancaster said.
Stress HormoneOne simple way to avoid inflammation is to avoid overeating. “If you eat too many calories, it can be hard for your body to regulate its blood sugar. And that leads to inflammation,” Lancaster said, adding that this kind of blood sugar-induced inflammation tends to affect the kidneys, liver, and pancreas.
When it comes to supplements, Lancaster is ambivalent. But she admitted that when she gets sick herself, she takes zinc lozenges. She cited some inconclusive evidence that Vitamin C may have some antiviral properties or may be simply reducing inflammation across the body.
Cortisol is another of the body’s loud alarm bells. It is our primary stress hormone, and according to Lancaster, it can cause “drastic changes to the way that your cells can function on a genetic level.” A burst of cortisol here or there can help you spring into action to avoid a threat, but too much, too often can leave your body stuck in an uncomfortable, unhealthy kind of overdrive.
Lab research shows that immune cells can't fight viruses as well when they are injected with cortisol. In 2018, researchers at the University of Kent found cortisol levels to be a critical factor at play in leukemia cases, showing that the stress hormone hinders the immune system’s ability to incapacitate intruders before they really get destructive.
Reading, meditating, and especially exercising may lower cortisol levels in people.
Exercising has the added benefit of helping you get your eight hours of sleep, all of which helps reduce inflammation and regulate stress hormones. Last week, a cardiovascular researcher at the University of Virginia released findings suggesting that an antioxidant that is naturally released during exercise can significantly reduce the risk of suffering from acute respiratory distress syndrome, a severe problem that occurs in 20 to 42 percent of hospitalized COVID-19 patients. Exercise, the research found, boosts production of an antioxidant known as extracellular superoxide dismutase, or EcSOD, which "hunts" atomic free radicals that can harm the body's cells.
Beth Jacobs, a nutritional epidemiologist at the University of Arizona, is wary about making any promises about how any type of immune boosting can influence one’s chances of coming down with a bad case of the virus.
"We know essentially nothing about COVID19 yet," she said in a recent interview.
In lieu of more specific knowledge about the virus, she echoes Lancaster’s sentiments about the importance of healthy habits. When it comes to immunity, she said, it is all about the “three interlocked concepts, which are diet, physical activity, and sleep.”
“Essentially, [sleep] is the time when you're repairing what's happened during the day,” Jacobs said. “It allows you to heal up to take on the next day.”
While science has yet to uncover the inner workings of sleep, Jacob says we can infer its value from its incredible cost. Our ancient ancestors risked being eaten while they laid motionless for hours a day for it, she pointed out.
She urges persistence and patience in developing new, healthy habits, stressing that we are still at the “very beginning of the pandemic.” Try new recipes and get outside, Jacobs urged.
“Use the time to go outside and walk," she said. "And if you've never walked before, just take a 10-minute walk, and then a 15-minute walk next week. Just keep going."