Go Ad-Free
logoThe People's Perspective on Medicine

New Evidence on the Value of Face Masks

Large studies demonstrate the value of face masks in reducing viral transmission among close contacts. COVID cases are now low.

One of the first tools people used to try to cut the transmission of COVID-19 was the very old practice of covering the nose and mouth with a mask. During the 1918 influenza pandemic, public health officials also used masks to try to slow the spread of the disease. In those day, however, face masks were pretty crude. They were made out of gauze or cheesecloth. The value of face masks made of such materials was questionable.

Even then, Americans resisted face masks. Public health authorities called the refuseniks “slackers.” Some people were fined or even jailed if they did not wear masks. Not surprisingly, face masks became highly politicized in the fight against the influenza pandemic of 1918 and 1919. Many people resisted masking. There was even an “Anti-Mask League” that insisted masks were ineffective and inconvenient and should be rejected.

People Still Argue About the Value of Face Masks:

We have heard from a lot of people who share the same perspective today as the Anti-Mask League of a century ago. These people insist that even N95 face masks are worthless at best and counterproductive at worst.

Greg offers his opinion on the value of face masks:

“The data suggest that both medical and non-medical face masks are ineffective to block human-to-human transmission of viral and infectious disease such as COVID-19. Wearing face masks has been demonstrated to have substantial adverse physiological and psychological effects. These include hypoxia, hypercapnia, shortness of breath, increased acidity and toxicity, activation of fear and stress response, rise in stress hormones, immunosuppression, fatigue, headaches, decline in cognitive performance, predisposition for viral and infectious illnesses, chronic stress, anxiety and depression.”

A lot of visitors to this website offer strong positions on controversial health issues. They frequently maintain that “the data suggest…” What data? Where? Did it come from a source other than YouTube?

I guess Greg would not want his surgeon to wear a face mask during an operation, since doing so might lead to a “decline in cognitive performance.” That would not be good during delicate surgical procedures. Then again, catching an infection would not be so good either. Is there any hospital that would allow surgery if doctors and nurses refused to wear face masks?

Data Published in Reputable Journals:

A study published in Baylor University Medical Center Proceedings (Feb. 23, 2023) concludes that:

“Regarding cognitive performance in this cohort, neither reaction time nor accuracy were significantly impacted by wearing a CFM [cloth face mask] during rest, submaximal exercise, peak exercise, or recovery. These results align with recent literature describing cognitive performance outcomes while wearing a face mask during a mental load.”

Do Quality Face Masks Prevent Infections?

Before I attempt to answer this question there are several important caveats. Not all masks are created equal! Many of the masks that people have worn were created with materials that are unlikely to stop small virus particles.

More important, people rarely wear masks snugly around their face with elastic bands that go over and behind the head. If there are gaps around the nose, cheeks or chin, the mask is not going to work. Then there are the ways people wear face masks. The value of face masks will be subverted if someone wears a face mask below the nose, or worse, under the chin.

What Does Research Reveal on the Value of Face Masks?

JAMA Network Open published an article on October 31, 2023 titled:

“Masks During Pandemics Caused by Respiratory Pathogens-Evidence and Implications for Action”

The authors introduce the article with this thought:

“More than 3 years after the COVID-19 pandemic began, the use of face masks in the community remains controversial. Vaccination, treatment, population immunity, and other developments have enabled a return to a semblance of prepandemic life, but disagreement about what the evidence shows about masks—and the implications for their use—persists. SARS-CoV-2 is still a disruptive and deadly presence, and future epidemics or pandemics caused by pathogens spread by the respiratory route are a near certainty.1 Failure to understand the evidence on the role of masks in preventing the spread of SARS-CoV-2 could undermine our ability to respond to epidemics and pandemics caused by respiratory pathogens.”

After reviewing the available evidence, these researchers observe:

“Well-designed observational studies have demonstrated the association of mask use with reduced transmission of SARS-CoV-2 in community settings, and rigorous evaluations of mask mandates have found substantial protection…Masking in the community to reduce the spread of SARS-CoV-2 is supported by robust evidence from diverse settings and populations.”

They conclude:

“Available evidence strongly suggests that masking in the community can reduce the spread of SARS-CoV-2 and that masking with the highest-quality masks that can be made widely available should play an important role in controlling whatever pandemic caused by a respiratory pathogen awaits us.”

Other Studies Evaluate the Value of Face Masks:

Other studies have been published evaluating the effectiveness of face masks. Such assessments are difficult, because there are many different kinds of masks. Some may be more effective than others in protecting against an airborne virus. In addition, people vary greatly in how they wear masks.

One study examined SARS-CoV-2 in classroom air in two high schools in Switzerland (PLOS Medicine, May 18, 2023). The study took place between January and March 2022, when Omicron dominated. There was virus present in the air all through the study time frame. In the school that mandated mask wearing, however, the scientists detected 70% fewer viral particles. Air cleaners also lowered the amount of virus in the air by 40%. The researchers concluded that mask mandates reduced viral transmission in classrooms.

Another study analyzed three randomized clinical trials and 21 observational studies of masks (Annals of Internal Medicine, May 16, 2023). It was difficult to evaluate how the differences between cloth masks or N95 masks may have affected the outcome. However, the investigators determined that wearing masks leads to a modest reduction in COVID transmission in community settings.

An accompanying editorial in the Annals of Internal Medicine concludes,

“To get to the truth about masking, the authors say it is imperative to design studies that fill information gaps, interpret the evidence accurately, and are honest about what we do and do not know.”

Could the Value of Face Masks Lie in Stronger Immunity?

Researchers from McMaster University in Hamilton, Ontario, report another potential benefit of masking (Journal of The Royal Society Interface, May 4, 2022). Even if masks do not completely block viral transmission of SARS-CoV-2, they reduce the amount of virus a person inhales. As a result, people are less likely to become severely ill and require hospitalization. When the viral load is low, the immune system can respond more effectively and create antibodies that are capable of defeating the infection before it causes severe damage.

The scientists term this “variolation,” comparing it to the early methods of preventing smallpox before vaccines were invented. This research on revving up immunity with low-level exposure has important implications for future COVID variants as well as other respiratory infections.

Previous Views on the Value of Face Masks:

Throughout much of the pandemic, public health officials urged us all to use face masks, physical distancing and hand washing indoors to reduce the spread of COVID-19. Many individuals remain unconvinced of the value of face masks. They keep insisting that there is no scientific evidence for the value of face masks. Studies contradict that assertion with substantial evidence.

But not all masks are created equal. Many of the masks we see people wearing are almost useless. And when people wear them below their nose, it’s a joke.

People Who Wear High-Quality Face Masks Are Less Likely to Catch COVID-19:

Many people have complained about having to wear masks in public. However, the evidence is increasing that they make a difference. What do we know about the value of face masks?

Health care workers are especially vulnerable to COVID-19 if they haven’t been vaccinated. A study shows that the quality of the masks they wear makes a huge difference in their risk of catching COVID.

British researchers gathered information most of last year with regular COVID testing. During that time national guidance was for healthcare workers to wear surgical masks. Such face coverings don’t fit tightly and are not designed to block aerosolized virus particles.

Staff caring for patients infected with the coronavirus were 47 times more likely to contract the infection than those on non-COVID wards. However, after they switched to high-quality FFP3 respirators, the rate of infections dropped dramatically. These special respirators fit tightly and filter out aerosol particles. The investigators conclude that surgical masks are not adequate to protect against an aerosolized virus such as SARS-CoV-2 (Authorea preprint, June 24, 2021).

The Axios/Ipsos Poll:

An Axios/Ipsos Coronavirus Index poll starting in March of 2020 showed that only 11% of those who reported always wearing masks whenever they left home tested positive for COVID-19. On the other hand, 23% of those who rarely or never wore masks tested positive. The poll showed 12% of those who maintained at least a six-foot distance from others tested positive for COVID. In comparison, 20% of people who were less careful about social distancing became infected.

Although masks and social distancing are far from foolproof, they do appear to offer some protection against the transmission of SARS-CoV-2. A variant from India, B.1.617.2, also known as Delta, spread rapidly in Britain. It also spread widely in the US. For those who are not vaccinated, this highly transmissible variant posed a significant risk. Unvaccinated individuals who don’t wear face masks may want to reconsider, since the value of face masks is becoming increasingly clear.

Global Research on the Value of Face Masks:

A study published in BMJ Global Health (May 28, 2020) suggests that measures such as washing hands, maintaining distance and wearing face masks do indeed reduce the risk of spreading or catching the coronavirus.  Researchers tracked 335 people in 124 families in which one person tested positive for SARS-CoV-2. The goal of the study was to determine how many people in the families caught the virus. Scientists also wondered if there were any strategies that worked to prevent secondary infection within two weeks of contact.

Almost one fourth of the other family members became infected after contact with one ill member. The risk of transmitting the infection was highest before symptoms developed or early in the disease. This makes isolation or distance much more difficult to use effectively. However, when people in the family wore face masks, practiced hygiene and used good ventilation, they reduced viral transmission. When people were wearing face masks in the home as a preventive measure before the first family member got ill, other family members were 79 percent less likely to catch the virus. This certainly highlights the value of face masks.

If the initial patient had diarrhea, family members were four times more likely to get sick as well. However, disinfecting the bathroom and closing the toilet lid before flushing were helpful. These could be helpful tactics even after the pandemic has finished.

Another Study on Covering the Face:

A second study confirms the value of face masks. This meta-analysis of 172 studies found that wearing face masks and using eye protection can reduce the risk of contracting COVID-19 (The Lancet, June 1, 2020). Maintaining physical distance between infected and uninfected people was also critical.

Canadian investigators reviewed data collected from more than 25,000 volunteers in 16 countries. The researchers analyzed infection rates of coronaviruses including SARS, MERS and SARS-CoV-2. They found that maintaining at least three feet of distance was better than close contact. The farther away people were from each other, the lower the risk of viral transmission.

In addition, people who used face masks conscientiously were less likely to transmit the infection.

The investigators state that

“Face mask use could result in a large reduction in risk of infection, with stronger associations with N95 or similar respirators compared with disposable surgical masks or similar [reusable 12-16-layer cotton masks]. Eye protection also was associated with less infection.”

Because N95 respirators provide much stronger protection, all health care workers should have access to such protective gear. So should anyone who is at high risk for catching SARS-CoV-2. We only wish high-quality face masks were readily available for free or very low cost. If the future variants result in a resurgence of COVID cases, people will once again need to be careful when they are indoors.

Rate this article
4.2- 517 ratings
About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.”.
Tired of the ads on our website?

Now you can browse our website completely ad-free for just $5 / month. Stay up to date on breaking health news and support our work without the distraction of advertisements.

Browse our website ad-free
Join over 150,000 Subscribers at The People's Pharmacy

We're empowering you to make wise decisions about your own health, by providing you with essential health information about both medical and alternative treatment options.