"Masks lower your oxygen levels"

Some people performed tests like these to try to prove that masks do affect oxygen levels. Jeff Neff measured the oxygen levels of the air between his mouth and his mask; however, his reasoning is faulty. The air also contained his exhaled breaths, which have lower oxygen levels then inhaled air. These results don’t show the oxygen levels of the body, in other words the oxygen you’re actually getting. Oxygen molecules are still small enough to pass through the mask during inhalation, so you still get your oxygen when you wear a mask.

Many doctors, like Dr. Maitiu O Tuathail, performed tests while wearing masks to prove that masks don’t affect oxygen and carbon dioxide levels in your body. For more anecdotal evidence, doctors, surgeons, and construction workers wear masks all the time for long periods of time, and they’re just fine.

Wearing a mask does not affect your oxygen and carbon dioxide levels. While it may feel a little weird to wear a mask, they’re not made to keep the air out. Masks keep droplets from spreading when you breathe, sneeze, or cough in order to slow the spread of COVID-19 (and other diseases, like the flu).

Just make sure not to use filters that would actually deter airflow, like plastic bags. A cloth mask is generally enough for everyday use when you go shopping and the like.

Masks are just a placebo

Masks actually do work. In this study by a research team in Hong Kong, the researchers showed that masks helped reduce the transmission of coronavirus (and influenza) in the droplets the wearers expelled whenever they breathed or coughed.

Some people have said that masks are ineffective because the viral particles are too small to be filtered by the mask. While it may be true that the virus by itself is too small to be filtered, the virus doesn’t just travel on its own. The virus travels on droplets which are created when you cough or sneeze. To reiterate the words of Dr. Bell from the CDC, the droplets that the virus travels on makes the entire unit big enough to be filtered by the mask. The particles become big enough for masks to become effective.

Masks cause higher carbon monoxide levels

While carbon monoxide poisoning is dangerous, people do not exhale carbon monoxide; they exhale carbon dioxide. Wearing a mask does not put people at risk of carbon monoxide poisoning.