Experts: Face masks don’t deprive the brain of oxygen
COVID-19 has killed more than 1.1 million people worldwide, including more than 219,000 in the USA in less than a year. Despite data that masks slow the spread of the virus, skepticism exists regarding their use.
One claim that continues to surface in social media posts is that masks cause oxygen deprivation in the brain.
A viral Facebook post transcribing a video message by neurologist Margareta Griesz-Brisson, which was removed by YouTube for violating its terms of service, says masks can cause neurological damage, especially in children.
“The rebreathing of our exhaled air will without a doubt create oxygen
deficiency and a fl ooding of carbon dioxide. We know that the human brain is very sensitive to oxygen deprivation. There are nerve cells, for example in the hippocampus, that can’t be longer than three minutes without oxygen – they cannot survive,” the post said.
The Facebook user did not answer whether she fact-checked the information before creating the post.
Medical experts dispute claims of masks dropping oxygen to dangerous levels.
“While masks can block particles like respiratory droplets and aerosols that might contain coronavirus, they do not block gases like oxygen and carbon dioxide,” said Linsey Marr, a professor of civil and environmental engineering at Virginia Tech and an expert in airborne disease transmission. “A recent study of people wearing surgical masks while walking around found no significant changes in carbon dioxide in their breath nor oxygen in their blood, compared to walking without a mask.”
Jonathan Parsons, a pulmonologist at the Ohio State University Wexner Medical Center and director of the Ohio State Asthma Center, addressed those claims on the medical center’s website.
“Fortunately, the flurry of complaints has also given rise to a number of highly effective demonstrations in which medical professionals display their excellent oxygen levels while trying on different masks – and sometimes multiple masks at once,” he wrote. “Believe these demonstrations, because they’re true. Many professions require the regular use of masks, and the people who wear them don’t suffer as a result.”
The University of California-San Diego Health office posted a video on its YouTube page in which one of its demonstrators wore four masks at once and saw her oxygen level remain at 98%, according to a pulse oximeter, which measures oxygen saturation levels in the blood.
When she wore six masks at the same time, her oxygen levels dropped to 97%. Normal oxygen levels using a pulse oximeter range from 95%-100%.
“Masks are safe,” said Atul Malhotra, a pulmonologist and research chief of pulmonary, critical care and sleep medicine at University of California-San Diego Health. “The oxygen levels are stable. Carbon dioxide levels are stable. It does not impair breathing.”
The federal Centers for Disease Control and Prevention recommends wearing masks in public. It advises children under the age of 2 not to wear masks.
Nicole Iovine, an infectious disease expert and hospital epidemiologist at the University of Florida, said guidelines for children under 2 are not related to oxygen deprivation.
“One of the reasons is that they can’t wear it effectively,” she said. “They’re constantly touching their faces, so it makes it a moot point. We also don’t have a lot of masks that would fit a 2-year-old.”
Masks are safe for older children. “Masks will not affect your child’s ability to focus or learn in school,” according to the American Academy of Pediatrics. “The vast majority of children age 2 or older can safely wear a cloth face covering for extended periods of time, such as the school day or at child care. This includes children with many medical conditions.”
Experts dispute that wearing a mask leads to neurological damage, including in children.
“In order for them to have neurological symptoms, you have to have oxygen deprivation,” Iovine said. “There’s no evidence of that at all. If you’re going to have an effect, you need to have a cause.”
Studies have linked the virus itself to neurological problems, such as confusion, strokes and seizures.
A study published this month by researchers at the New York University Grossman School of Medicine found that one in seven infected patients experienced these issues.
“The neurological complications seen in COVID-19 are predominately the secondary effects of being severely ill and suffering from low oxygen levels in the body for prolonged periods of time,” Jennifer Frontera, a professor in the Department of Neurology at NYU Langone Health, said in a news release.
Iovine said research showed people were at a greater risk of experiencing the symptoms warned of in the post by not wearing a mask.
“The claims about wearing a mask is exactly the opposite of what the truth is,” Iovine said. “By not wearing a mask, there’s a greater chance of that happening.”
Our rating: False
Though the neurological damage described can occur when there is oxygen deprivation, medical experts say there is no evidence linking either to wearing masks.
Medical studies have shown a link between COVID-19 and those very neurological effects, meaning the decision to not to wear a mask puts people at a higher risk of experiencing them.