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Notice that the carbon dioxide levels in the air keep rising and rising? Along with the world getting hotter, the carbon dioxide levels are rising, and last year it hit 414.7 parts per million (ppm). This is the highest it has been in at least 800,000 years, and maybe for millions of years! (It's from the burning of fossil fuels.) Soo... the big question is: What will increasingly higher CO2 levels mean for our brains - for our thinking and cognition?

Ever notice that in rooms filled with people, that the air gets stuffier over time? Well, that's the effect of carbon dioxide - as the carbon dioxide levels rise (from us simply exhaling), the air in the room feels stuffier. It can already feel stuffy at 600 ppm. Rooms with people in them (classrooms, office meetings, etc) easily hit over 1000 ppm of carbon dioxide.

Studies suggest that at certain levels of carbon dioxide our thinking gets worse. While study results vary, there does seem to be agreement that "mental processes in the domain of decision making and planning appear to be robustly affected".  And yes, a growing number of studies do find pretty scary results.

For example, one 2016 study that looked at indoor air in office buildings found that: "...seven of nine cognitive function domains tested in a strategic management simulation decreased as CO2 increased. Employee scores were 15 percent lower in a day spent working at 945 ppm, and 50 percent lower at 1,400 ppm." It means that the people weren't thinking all that well as the CO2 levels rose in the air they were breathing.

Research looking at carbon dioxide effects have generally studied the problem as an "indoor pollutant" and used the outdoor air as a comparison. But what happens when the outdoor air of the future is the "high CO2" level studied today?

Some physical effects of rising carbon dioxide exposure in humans: increased CO2 in the lungs, in the blood, and in the brain (which is associated with reduced oxygen and brain activity), increased sleepiness and anxiety (both of which harm cognitive function), and acidosis (lowered blood pH - which leads to symptoms such as restlessness and a rise in blood pressure). One study in juvenile rats found "reduced levels of neuroprotective growth factor", which harmed brain development and impaired learning and memory.

What about babies and children? Developing fetuses? The elderly? The sick?  All unknown. Also, studies looking at effects are short term, but our future (if not changed) will have us exposed to higher and higher levels of CO2 all the time.

Keep in mind that as outdoor carbon dioxide levels rise, indoor levels will also rise.  Think about it - opening a window to let in some fresh air will only give you the CO2 levels in the outside air. If that is high and feels stuffy, that's what you'll get. All the time. Why isn't everyone discussing this issue? 

Excerpts from Robinson Meyer's article at The Atlantic: The Human Brain Evolved When Carbon Dioxide Was Lower   ...continue reading "What Will Rising Carbon Dioxide Levels Do To Our Brains and Thinking Abilities?"

This is a topic that is totally neglected: What will it feel like when the carbon dioxide levels in the atmosphere (the air) increase as our climate changes? What kinds of effects will it have on our thought processes (our cognition)? The reason I mention this is because research shows that as carbon dioxide (CO2) levels increase in rooms with people in them, it feels "stuffy" and people's thinking (cognitive processes) deteriorate. They don't think and work as effectively. Air starts to feel "stuffy" at about 600 ppm (parts per million). Our current CO2 levels in outside air are already above 400 ppm, and the levels are forecast to keep rising.

Indoor air typically has much higher CO2 concentrations than outdoor air because people are exhaling CO2 with every breath. (Note that research shows that urban city centers can already have outdoor CO2 levels above 500 ppm due to the “urban CO2 dome” effect, and elementary school classrooms are frequently above 1000 ppm, with some going as high as 3000 ppm at times). So as CO2 levels rise in the atmosphere with climate change, it will lead to even higher indoor CO2 levels in our workplaces, homes, and schools.

So... with increases in CO2 levels, what if it feels "stuffy" all the time? We won't be able to escape the "stuffiness" by going outside or opening a window. And remember, it will be worse in rooms with people in it, or in cars and aircraft. The research shows increasing CO2 levels make it harder to work and think effectively - think of it as an indoor air pollutant. Holy mackerel! This scary aspect of the effects of rising CO2 levels in the atmosphere needs to be widely discussed and addressed.

The following 2 articles discuss the research showing the negative effects on cognition with increases in CO2 levels (what happens to people's mental processes in crowded classrooms, offices, etc.).  ...continue reading "What Do High Carbon Dioxide Levels In The Air Do To Thought Processes?"

Research study after research study finds all sorts of health benefits from exercise. But what about the air quality in those stuffy crowded gyms, especially those in already polluted areas? From November 2014 NY Times:

The Bad Air in Our Gyms

But a new study of air quality in gyms raises some interesting questions about whether the places in which we work out are as healthy as they should be. Science and common sense tell us that exercising in polluted air is undesirable. People who frequently run alongside heavily trafficked freeways and breathe great lungfuls of exhaust have been shown to have an increased risk of heart disease, even if they are otherwise in admirably good shape.

...researchers at the University of Lisbon in Portugal and the Delft University of Technology in the Netherlands decided that they would place air-quality monitoring equipment in gyms throughout LisbonPortuguese fitness sites are similar to those in the United States, said Carla Ramos, a graduate student at the University of Lisbon who led the new study. Most feature a weight room and multiple, smaller studio spaces for aerobics classes, yoga sessions and similar programs.

For the new study, Ms. Ramos obtained permission from 11 Lisbon gyms to position air-quality monitors in each site’s weight room and several studios. The machines were set to measure pollutants during the late afternoon or evening hours, when the gyms were at their most crowded. For about two hours at each gym, the monitors measured the levels of commonly found indoor pollutants. These include carbon monoxide, carbon dioxide, ozone, airborne particulates such as dust, and various chemicals released by carpeting, cleaning products, furniture or paint, including formaldehyde.

To gain even more detailed readings, the scientists subsequently placed additional monitors in three of the gyms, which measured air quality throughout the building and throughout the entire day.Then they checked the pollutant levels from all of the gyms.

Their findings were disquieting. In general, the gyms showed high levels of airborne dust, formaldehyde and carbon dioxide. The concentrations of these substances generally exceeded most accepted standards for indoor air quality. (No government agency in the United States formally monitors air quality in gyms.) The levels were especially high during evening aerobics classes, when many people were packed into small studios, stirring up dust and fumes and puffing heavily, producing carbon dioxide with every breath.

The high concentrations of dust and chemicals like formaldehyde in the air at the gyms represent perhaps the greatest potential concern, Ms. Ramos said. In sufficient concentrations, these substances can contribute to asthma and other respiratory problems, she said. Almost all of the gyms in the study had levels of these substances that significantly exceed European standards for healthy indoor air standards.

Carbon dioxide, though not toxic to people, could also be cause for concern. In high concentrations, Ms. Ramos said, it has been found to contribute to bodily fatigue and cognitive fogginess, neither of which is desirable during a high-intensity aerobics class. Elevated levels of carbon dioxide can also indicate a poorly ventilated building, she said, especially if they remain inflated for hours, as they did in her study.

“We consider that the gymnasiums meet the criteria for a poor indoor quality,” Ms. Ramos said. Poor indoor air quality is a particular issue in gyms, of course, because people there tend to be breathing heavily. “When we exercise, we take in more air with each breath and most of that air goes through the mouth, bypassing the natural filtration system” in the nostrils, Ms. Ramos said. “The pollutants go deeper into the lungs compared to resting situations.”

The findings should not, however, discourage anyone from visiting a gym, Ms. Ramos said. None of the sites in the study had measurable levels of carbon monoxide, she pointed out, one of the most dangerous of known air pollutants.