Study: Masks Don’t Increase Your CO2

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I honestly love cringe. Scripted cringey TV shows like Curb Your Enthusiasm were eventually not enough for me so I turned to “reality” shows like 90 Day Fiance, and honestly my addiction grew to the point where even that wasn’t enough. Like, I can’t sit there and watch an entire hour of garbage TV just for a few golden moments of cringe. So now I also enjoy (and, admittedly, sometimes seek out) pure undiluted real cringe on YouTube and TikTok. And COVID-19 has overwhelmed me with the cringey content I wanted — especially when it comes to people who hate wearing masks. Like, who could even see that one coming? It’s a mask! It’s not a big deal. But never put it past people to be stupid about the stupidest things. While that’s been bad for the spread of COVID-19 through the US, it’s been great for cringe videos. Here’s one you’ve probably seen: “I don’t wear a mask for the same reason I don’t wear underwear: things gotta breathe.”

Here’s a slightly less, uh, colorful woman with similar concerns  (3:30): “Where do you get the authority to reduce my oxygen?”

And this is all just from one meeting, in Palm Beach, Florida. Thousands of people around the country are saying the same thing: masks reduce your oxygen and cause harm.

Here’s the thing, obviously most people know this isn’t true. I’d guess that even a lot of the people who are saying it know it’s not true. We know it’s not true for several reasons, without even thinking about it very hard. For a start, we know that medical professionals wear masks all day long in strenuous environments and have been doing so since the mid 19th century. If wearing masks caused physical problems, we would know it by now because there would be millions of doctors and nurses dying of oxygen deprivation after a 12-hour shift.

We also know it’s not true because we know that oxygen deprivation gets you high. I’ve known this since the 7th grade, when my classmates started purposely hyperventilating to get a quick high. Hey, give them a break — weed was very difficult to get back then.

If wearing a mask got you high then COVID-19 would never be able to gain hold in America’s high schools because every student would be diligently wearing their mask and sailing through their classes in a blissful haze.

If wearing a mask restricted oxygen, erotic asphyxiation enthusiasts would be rejoicing over finding something to get off to that’s way safer than choking each other with belts.

So we know, through common sense, that masks don’t significantly affect how much oxygen a person gets. But what about this lady’s point, who says (2:30): “How about people who can’t breathe? With the myriad of conditions that there are, not just one not just two maybe four maybe five.”

Are there people out there who could be hurt by masks? Let me say up front that this should work like vaccines: there are people out there who cannot get vaccines because they’re immunocompromised. That doesn’t mean that no one should get vaccines — it actually means the opposite. It means everyone who CAN get a vaccine SHOULD get a vaccine, because doing so will protect the people who can’t get them. If there are people who can’t wear masks, it means it’s more important than ever for everyone else around them to wear masks, to protect everyone.

But, are there people who can’t wear masks? Dr. Michael Campos is a pulmonologist (aka a doctor who specializes in the human respiratory system) at University of Miami and he saw the video of his neighbors complaining about masks, so he decided to conduct a small study about how masks can affect your oxygen levels. He and his colleagues recruited 15 people in their 60s and 70s with severe chronic obstructive pulmonary disease, all of whom had less than 50% lung function. The most common symptoms of COPD are shortness of breath, cough, wheezing, and chest tightness.

Those 15 people were joined by 15 healthy volunteers in their 30s, not so much as a control group but to evaluate whether or not masks affected the oxygen levels in healthy people. Everyone wore surgical masks for half an hour and then went for a 6-minute walk while still wearing them. The 6-minute walk is a standard procedure the doctors use to determine whether or not their COPD patients need long-term oxygen, so this was considered an observational study.

The subjects’ blood was then drawn and tested to see how much oxygen and carbon dioxide was in their system. The researchers found that the masks did not lead to a significant increase in CO2 in either group. There was an expected drop in oxygen from the COPD group, which is expected with their advanced condition. The researchers point out that ideally they would have had a control group of COPD patients who exercised without masks to precisely compare the O2 drop between patient groups, but with a pandemic on it would be extremely unethical to allow these patients to walk around and interact with doctors without masks on.

And that’s the real takeaway here: doctors agree that not only do masks not increase CO2 in patients with lung problems, but it’s those patients who are most at risk from this virus because of their lung problems, and so they and the people around them all must wear masks at all times when in public.

This was a small observational study without a proper control group, but remember that it matches our common sense observations. Extraordinary claims require extraordinary evidence, and conversely common sense claims, like “surgical masks don’t significantly impact your oxygen intake,” can be supported with ordinary evidence. At this point it’s on the anti-maskers to present evidence for their extraordinary claim that masks are killing people left and right. I…won’t hold my breath.

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

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One Comment

  1. It’s funny also how people in Japan, Korea, Thailand, Vietnam, Laos and Cambodia are dropping dead like flies from asphyxiation because they ALL wear masks, while all the big tough herd mentality types in the West are surviving so well because they refuse to wear a mask ever. \sarcasm

    Makes me ashamed to be a Westerner tbh

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