Fact check: Face masks do not cause “terrible damage” to the brain by depriving it of oxygen

A video being shared online has falsely said face coverings do nothing to stop the spread of the novel coronavirus and will instead deprive the brain of oxygen, causing damage to adults and developmental issues in children.

Reuters Fact Check. REUTERS

The 55-minute video, uploaded to Bitchute, features known British conspiracy theorist David Icke (here, here) and his son Gareth, who discuss topics including the effect of face coverings during the COVID-19 pandemic, masculinity and censorship. Among other claims outside the scope of this check, the pair says several times throughout the video that face coverings can cause brain-damaging oxygen deprivation.

Icke begins by quoting a video from German doctor Margareta Griesz-Brisson, the founder and medical director of the London Neurology and Pain Clinic (here), who questions the safety of face masks. The original video has been removed from social media, but can still be viewed in German (here), and with an English translation (here) .

Icke takes quotes from several points in the video: “Everyone should be exempt from wearing [masks], she says, because oxygen deprivation is dangerous for every single brain. It must be the free decision of every human being if they want to wear a mask, which is absolutely ineffective to protect themselves from a virus.”

Moving to the effects on children and teenagers, Icke quotes the doctor as suggesting it would be “absolutely criminal” to deprive youth of oxygen by forcing them to wear face coverings as it “inhibits the development of the brain”.

“When ten years has passed, dementia is going to increase exponentially and the younger generations couldn’t reach their God-given potential,” Icke quotes the doctor further, before adding his own opinion: “So, parents, your children should not be going to school if they have to wear masks. And the general population, you should not be wearing masks if you want to protect your brain […] It is only going to end one way. Total subjugation of a population who cannot think properly because the brain hasn’t formed as it should because of oxygen deprivation when they were young.”

Firstly, there is no evidence to suggest face masks cause oxygen deprivation that is “dangerous” to adult brains or that prevent a youthful brain from developing properly. A study from U.S. researchers in July found an average face mask did not limit the flow of oxygen to the lungs – and even in test subjects with severe lung diseases (here). The researchers noted that any initial discomfort from wearing a mask was possibly due to the irritation of sensitive facial nerves, its warming of inhaled air, or feelings of claustrophobia.

Reuters has previously debunked claims that face masks cause hypercapnia, a condition that develops after inhaling too much carbon dioxide (here) .

A representative from the U.S. Centers for Disease Control and Prevention (CDC) told Reuters: “The CO2 will slowly build up in the mask over time. However, the level of CO2 likely to build up in the mask is mostly tolerable to people exposed to it. You might get a headache but you most likely [would] not suffer the symptoms observed at much higher levels of CO2. The mask can become uncomfortable for a variety of reasons including a sensitivity to CO2 and the person will be motivated to remove the mask. It is unlikely that wearing a mask will cause hypercapnia.”

Meanwhile,, a global team of public health experts, said wearing a mask is considered safe and effective for most people: “Wearing masks is generally considered safe for children and adults. There are a few exceptions, for very young children (under two years of age in the United States) and people with health conditions that make it difficult to wear a mask (ex. certain pre-existing pulmonary or cardiac issues, mental health conditions, developmental disabilities). For the vast majority, wearing masks is an effective way to help reduce COVID-19 transmission without causing any major side effects, as long as masks are kept clean and used correctly.”

The World Health Organisation (WHO) recommends children over 12 should wear a mask under the same conditions as adults, while those between 6-11 should wear them based on a number of limited factors. Children aged 5 and under are not recommended to wear them “based on the safety and overall interest of the child and the capacity to appropriately use a mask with minimal assistance” (here). National health authorities have differing mask requirements, but the lower-limit is often set due to concerns surrounding “choking and suffocation” (here) in very small children.

Lastly, it is untrue to claim masks are “absolutely ineffective” protection from COVID-19. Masks are recommended as a preventative in conjunction with other methods – such as social distancing – when trying to stop the virus from spreading (here). In June, a review of 172 studies found distancing, masks and eye protection pooled together as a preventative method worked well to cut the risk of infection (here). The authors said, however, that further high-quality research studies into the effectiveness of different types of mask were "urgently needed".


False. There is no evidence that face masks cause oxygen deprivation that damages brains or limits development. It is also inaccurate to say face masks have no effect on limiting the spread of COVID-19. Research shows masks can be an effective way to prevent transmission when combined with social distancing and eye wear.

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