Years ago, I was visiting Cuba with my new boyfriend. By our last day I was running a fever (in the mornin’, a fever all through the night). I had the flu. I slept the entire flight home with my head on his shoulder. The next day he had the flu too, so we spent the week eating soup in bed and taking care of each other. It all felt very romantic. 

But the honeymoon phase ends. Now that I live in reality again, getting sick for me starts with denial, moves through the five stages of grief until reaching acceptance, and is punctuated by googling “flu vs. cold vs. covid symptoms” for the 50th time. Which is to say: it is not fun and it is definitely not romantic. So what do I do to avoid this experience?

You’re likely familiar with the foundational pillars of a healthy immune system: sleep, exercise, nutrition, stress management, and social connection.

Still, trying to avoid getting sick in the winter can feel like trying to find the exit at IKEA: you follow the arrows, take precautions, but somehow always end up lost in the kitchen section again. 

Are you really doomed if you touch your face?

We touch our faces 20-70 times per hour and ~50% of these touches are to the eyes, nose, or mouth (entry points for infections). We’re especially likely to do this after shaking hands, which scientists believe is our way of “sniffing” the other person’s scent. Check out this phenomenon in action:

This behavior isn’t unique to humans. For example, when elephants meet, they often extend their trunks to touch and then bring them back to their own mouths for analysis. 

Face touching is likely rooted in evolutionary biology and is a very difficult habit to break. I could tell you to stop but this would be like telling my parents to stop taking the mini hotel shampoos. And…

What if face-touching is built into our behavioral blueprint because it’s actually beneficial, even necessary, for our health? Science supports this: face-touching is critical for facial microbiome diversity, communication, self-soothing, and more.

My approach is pretty simple: I regularly wash my hands year-round and I avoid touching my eyes, nose, and mouth when infection risk is high (e.g. during cold and flu season or at a crowded event). Beyond that I don't obsess about it. With the pace of AI these days, sometimes I have to touch my own cheek just to confirm I still exist.

Other ways to stay healthy:

In addition to the basics, here are three biohacks I use to further reduce my chances of catching a bug: 

Breathe through your nose instead of your mouth

Fascinating research is demonstrating the immune benefits of nasal breathing.

The mucosa and hairs of the nose provide powerful filtration and the nasal microbiome is uniquely designed for immunity, with sensors that detect viruses, bacteria, and fungi and release antimicrobials to defend against them.

Nasal breathing also triggers the release of nitric oxide gas into the airways, which is a potent antiviral and antimicrobial and has been associated with fewer cold symptoms and faster viral clearance.

Eat more fermented foods

Believe it or not, yogurt can reduce your risk of getting sick. Fermented foods directly increase immune function by strengthening the gut microbiome, reducing inflammatory markers, and ramping up white blood cells. Aim for 2-4+ servings per day, but any amount is better than nothing. Here are some ideas:

Notes: 1) While Kombucha is fermented, most store-bought brands are high in carbs and/or sugar, 2) Most pickles are pickled, not fermented (if vinegar is on the ingredient list, it’s pickled)

Take a hot shower or bath

Heat exposure has many benefits, including better sleep and reduced stress, which are both critical for the immune system. Direct links to improved cellular defenses are also being explored: in one interesting study, athletes had increased levels of circulating white blood cells after a single 15-minute sauna session followed by a cool-down period.

Next time you need an immune boost, take a 15-30 minute bath or shower in the hottest water you can tolerate (or use a sauna). Optional: follow with a cold shower.

Eventually cold and flu season will pass. In the meantime, may we all have a week filled with strong immune systems, contagious laughter, and easy Ikea runs,

Dr. Lauren Kelley-Chew
@drkelleychew

I’m a Stanford and Penn-trained MD and health tech founder with over a decade working on health optimization in Silicon Valley. Biohacking for the Rest of Us is my answer to medical elitism – I want all people to have access to cutting-edge science that can dramatically improve their health.

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