In the span of a year, the coronavirus has spread to 192 countries, has infected over 285 million people and has claimed more than five million lives around the world. But based on the news coverage, you might think that the only preventive measures we can take are social distancing, wearing masks, washing our hands regularly, and trying not to touch our face.

These are, of course, all essential steps. But we need to expand the conversation to make room for a crucial aspect of health that has received very little attention: one of the best things we can do to protect ourselves is to proactively strengthen our immune system. 

This is beautifully captured in The Lucky Years, by Dr. David Agus (who is also on Thrive’s board of directors): "If you throw a lit match into a dewy wet forest, what happens? Nothing. But toss that same incendiary device into a parched landscape that hasn’t seen rain in a long time, and you’ll soon have a quickly moving fire on your hands. The difference between these two environments — one damp and saturated and another dry and thirsty — means everything in terms of how they respond to that spark.”

Dr. Agus’s metaphor is an eloquent way of saying: the strength of our immune system matters greatly in our fight against disease. The inner environment we cultivate can truly make a difference. 

As The Washington Post puts it, “the severity of the symptoms depends highly on the patient’s age and immune system.” There is nothing we can do about our age. And there is nothing we can do about how fast the virus spreads or where it goes next. But there is a lot we can do to strengthen our immune system. And at a time when so much is out of our control, this gives us agency. 

Early studies of the virus have shown that people with pre-existing illnesses are more likely to become ill and die: “For the elderly and those with underlying heart disease, diabetes or other conditions, coronavirus can cause pneumonia and lead to organ failure and death.” It illustrates the difference between the two environments Dr. Agus describes. (For perspective, about 60% of American adults have at least one underlying health condition, according to Tom Frieden, former director of the Centers for Disease Control and Prevention.)

Here are some of the most important healthy habits we can add to our lives to build domains of protections that promote an adaptive immune response to challenges. These, of course, are habits that are very important to our health at all times. But now there is an extra urgency to adopting them.

Sleep is as important for our bodies as it is for our minds. For instance, we may not have a cure for the common cold yet, but we do know how to increase the likelihood of getting one: don’t sleep. Researchers at the University of California, San Francisco and Carnegie Mellon University monitored the sleep of participants for one week. Test subjects were then given nasal drops containing the common cold virus. Those who had slept less than six hours a night the week before were four times more likely to catch the cold compared with those who got more than seven hours of sleep. 

Another study from the University of Tübingen in Germany found that sleep gives the immune system a chance to regroup. And a study from the University of Washington Medicine found that chronic short sleep shuts down programs involved in immune response.  

And as neuroscience professor Matthew Walker puts it in his book Why We Sleep: “No matter what immunological circumstance you find yourself in — be it preparation for receiving a vaccine to help boost immunity, or mobilizing a mighty adaptive immune response to defeat a viral attack — sleep, and a full night of it, is inviolable.”

Beyond sleep, staying hydrated and making healthy food choices like avoiding processed foods is critical to boosting our immune system. And as a study from Stanford shows, avoiding sugar can help us reduce chronic inflammation, which contributes to the conditions that put us at greater risk for viral infections. And it can help us fight off obesity, which has been found to be linked to the severity of viral infections.

Finally, a big suppressor of our immune system, as Dr. Caroline Sokol says, is stress. And stress, of course, has cumulative effects on our ability to fall and stay asleep, and on our impulse to stress-eat or drink too much. And here is the coronavirus paradox: every day we are exposed to a constant stream of coronavirus news, but instead of easing our worries, the flood of information about new cases, some of them close to our homes, event cancelations, stock market drops, etc. etc., only makes us more stressed, which in turn suppresses our immune system. As the psychologist Neil Fiore puts it, “calling up the stress response to deal with dangers that are not happening now is similar to pulling a fire alarm for a fire that may happen next year. It would be unfair to the fire department and a misuse of its time and energy to ask firefighters to respond to such an alarm, just as it’s unfair to demand that your body continually respond to threats of danger from events that cannot be tackled now.”

That’s why it’s so essential to build practices and mental habits that protect us from cumulative stress and anxiety. Focusing on what we are grateful for and avoiding negative fantasies based on fear rather than data is as important for our mind as sleep and healthy food choices are for our body.

And as so much recent science has confirmed, we have more control than we realize when it comes to building healthy habits and resilience. So when so much of the coronavirus crisis is outside our control, it’s not only essential, but empowering, to focus on what we can control, which is more — much more — than washing our hands. 

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