Why You Don’t Need a “Strong” Immune System

This post contains a video, which you can also view here. To support more videos like this, head to!

This past January I decided that with another 6 months or so of quarantine ahead, I had just enough time to get RIPPED. I don’t mean skinny, I mean RIPPED, like doing, I don’t know, one pull-up. It’s been 4 months and I’m currently able to do zero pull-ups but I CAN dangle from the pull-up bar for a lot longer than I could back in January and you think I’m joking but I’m not. I feel STRONG and it’s great. I am even considering starting to look into protein powders. That’s how interested I am in getting stronger.

However, there is one way in which I am not overly concerned about getting stronger, and it may surprise you to learn that I’m talking about my immune system. That’s right: I would rather have strong biceps than a strong immune system.

I’m thinking about this right now because I am incredibly privileged to have been able to get my COVID-19 vaccine last week. I live in the Bay Area, where they are making certain zip codes eligible for vaccines leading up to April 15 when all adults will be able to get their vaccine. For those of you who are currently eligible or about to be eligible and are having issues finding an appointment, let me tell you that the secret is to not use the website, and to instead call your local vaccine distribution hotline and talk to a human. MyTurn sucks — when I tried it, it showed no appointments anywhere in my region. When I spoke to a human, she told me they had LOADS of appointments and she was able to book me one a few miles away from me within the hour. I know, we all think that talking on the phone is the worst, but the actual worst is dying in a pandemic. 

I got the Johnson and Johnson vaccine, which is a single dose that becomes more and more effective as time goes on. As I mentioned in a previous video, I’m not worried about the relative efficacy rates of the three approved vaccines — go check that out for more information but the short explanation is that Johnson and Johnson was tested long after the Moderna and Pfizer vaccines during a particularly bad COVID surge with several new variants, so you can’t compare the efficacy rate of each vaccine as though it’s apples to apples. In the real world, though, it appears that all the vaccines are equally great at keeping people alive and out of the hospital.

Personally, I’m quite happy that I don’t need to have a second shot in two weeks and that my side effects were just being a bit tired for a day.

While Moderna and Pfizer use new mRNA technology to deliver instructions to our immune system on how to attack COVID-19, the J&J vaccine is a more “traditional” vaccine that uses an inactivated cold virus (not COVID-19) to deliver the instructions. The end result is more or less the same: over the next few weeks and months, my body will continue to ramp up efforts to recognize and attack and kill COVID-19 if it ever shows up in my body. Good job, immune system!

A lot of people seem to be wondering whether or not they should keep wearing masks and socially distancing after they’re vaccinated, and let me be clear: yes, you absolutely should! No COVID-19 vaccine is 100% effective at stopping the spread of the virus — it significantly reduces your chances of catching it and makes your symptoms much less worrisome if you do catch it, but there is still that slim chance that you can catch it and pass it on. Combine that with the fact that a significant portion of people — mostly white conservatives in the United States — are refusing to get the vaccine, and you have a situation where to truly be rid of COVID we’re going to have to continue to be careful. You can hang out with your vaccinated friends, but if you’re going to be indoors around strangers you will want to continue wearing a mask to protect yourself and others.

But also, as I pointed out on Twitter, I have not had so much as a head cold since 2019. It turns out, COVID-19 aside, people are disgusting germ factories. This is a fact that Asian cultures have known for quite some time, which is why even before the pandemic they had already normalized wearing a mask when you’re out in public, especially if you aren’t feeling well. I hope that this becomes the norm around the world but even if it doesn’t, I will be regularly wearing a mask when I’m inside around strangers. Public transportation? Mask. Movie theater? Mask. Concert? Mask! Restaurant? Take-out. Seriously I do not see me happily eating inside a restaurant anytime soon 

In reply to my Tweet about this, someone brought up this thought: “what about keeping your immune system strong?”

It’s a fair question! We are constantly bombarded with messaging saying we should do everything we can to strengthen our immune system, and a lot of people believe that this means we will be healthier if we expose ourselves to more germs. Even I have always had this idea that the reason I don’t have any allergies is because as a kid I was constantly outside playing in the dirt and interacting with a wide variety of wild and domesticated animals. 

This is known as the “hygiene hypothesis,” and it’s been around for quite awhile as scientists have noted that, for instance, wealthy people in the late 1800s were more likely to experience hay fever than farmers.

There is some compelling evidence that the hygiene hypothesis is true, at least in part: research has shown that people like me who grow up in rural areas ARE actually less likely to experience allergies and asthma. However, a lot of other research shows that this is probably not due to exposure to dangerous infections — study after study after study has shown NO link between childhood exposure to viral infections and development of asthma or allergies, and at least one study of 200 children found that viral infections were actually associated with kids being MORE likely to develop asthma.

So why would playing in the dirt as a kid be good and protective, but actually getting sick is bad? The current most likely explanation is that it’s due to exposure to “good” microbes — germs that don’t actually harm us. Why? Because our immune system learns that it doesn’t have to attack every microbe it sees!

And that’s why I responded to that question about a “strong” immune system by saying “you don’t need a strong immune system, you need a balanced immune system.” A “strong” immune reaction is why your nose runs and you feel like shit when you have a cold — that’s your immune system responding to a threat. And that’s why for many people, your nose runs and you feel like shit just because it’s spring: your immune system is TOO strong. It’s going to war against literal flowers because it thinks everything is a threat. And that’s why doctors have established an entire category of disorders known as “autoimmune diseases,” in which your immune system is SO STRONG that it attacks YOU, like when Type 1 diabetes attacks your pancreas.

It’s like this: imagine you have a home that you want to protect from intruders, so you get a puppy that you want to train to be a really strong dog. And as a puppy, your house has several burglars break in and you train your puppy to attack them. But! You are a sad person who has no friends come over for that entire time. When the dog grows up, your mom decides to drop by because she’s worried about you because you have no human friends, but as soon as she walks inside, your dog attacks her because as a puppy he learned that anyone who comes through that door is a threat. Now even your mom doesn’t want to see you.
You don’t want a dog like that! You want a balanced dog who can tell the difference between a friend and a threat. ANd that’s why over on Twitter I said, that the best way to build a *balanced* immune system is to “treat your body well and avoid exposure to disease.” By “treat your body well” I mean eat a balanced diet, go for walks or whatever other kind of exercise you enjoy doing regularly, drink water, and get plenty of sleep. You can safely ignore all the things that promise to “boost” your immune system, like Airborne and Emergen-C, which are mostly just vitamins you will pee out. But if your body is in decent shape, it will be more likely to have the resources to respond to a threat when it encounters one. By “avoid exposure to disease” I mean just that: wash your hands after you use the bathroom, after you’ve been outside, and before you eat. Try not to touch your face after shaking hands or opening a shop door. Wear a mask, especially during a pandemic or in the winter when influenza is most likely to lurking. And get your vaccines for COVID, seasonal flu, whooping cough, and diphtheria. The vaccines don’t expose your body to infection, they simply give your immune system the instructions they will need if they do encounter that infection. And that will keep everyone safer, despite what you may hear from anti-vaccine and pro-disease laypeople on social media.

Rebecca Watson

Rebecca is a writer, speaker, YouTube personality, and unrepentant science nerd. In addition to founding and continuing to run Skepchick, she hosts Quiz-o-Tron, a monthly science-themed quiz show and podcast that pits comedians against nerds. There is an asteroid named in her honor. Twitter @rebeccawatson Mastodon Instagram @actuallyrebeccawatson TikTok @actuallyrebeccawatson YouTube @rebeccawatson BlueSky

Related Articles


Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Back to top button