Carbon dioxide harms your brain, your body, and your performance

When people talk about climate change and the constantly rising level of carbon dioxide in the air, they usually discuss the storms, droughts, fires, rising temperatures, and failing agriculture. However, something else about it is even worse.

Carbon dioxide is our own bodily exhaust gas. It is what we breathe out (4-5%), and it is quite toxic to us. The more carbon dioxide in the air, the more it gradually poisons us. Beyond a certain concentration, it is literally lethal.

People incorrectly think that humans suffocate in an enclosed space by running out of oxygen. In reality, suffocation is normally caused by carbon dioxide, not by having used up all the oxygen. Breathing produces carbon dioxide, and without ventilation, the concentration of carbon dioxide rises to a lethal level long before the oxygen level drops to zero.

If you are inside a room containing more than 10% carbon dioxide in the air, you will suffer convulsions, coma, and death even if the amount of oxygen is normal. If the concentration of carbon dioxide is 30%, you will lose consciousness and fall to the floor within seconds. You will be dead shortly thereafter.

Detrimental effects begin to occur long before the lethal dosage is reached:

• 0.2% = Reduced cognitive performance, more mistakes.

• 1% = Drowsiness, lethargy.

• 3% = Reduced hearing, increased blood pressure, mild narcosis.

• 5% = Confusion, headache, dizziness, breathlessness.

• 8% = Dimmed sight, muscular tremors, sweating, loss of consciousness.

• 10% = Convulsions, coma, and death.

• 30% = Loss of consciousness within seconds, followed by death.

Putting carbon dioxide in the air is like attaching a tube to a car's tailpipe and feeding it back into the engine's air intake. When a car engine breathes its own exhaust, it fails. The same thing happens with humans.

The deniers of global heating are like people that are stubbornly determined to connect a pipe between their anus and mouth so that they can breathe in their own farts.

Actually, carbon dioxide is the exhaust from our upper body rather than our lower body, therefore it is like the deniers want to connect a pipe between their nose and mouth so that they can breathe in via their nose the carbon dioxide that they breathe out via their mouth. This is madness, but they are extremely insistent about doing it anyway.

How to ventilate your rooms/office

If you work at your desk in your office/room with all the windows closed (and no other source of ventilation), and if you are the only person in the room, then your breathing will cause the carbon dioxide concentration to rise to a level that degrades your cognitive performance within approximately 2-3 hours (or more or less depending on the size of the room and your individual sensitivity).

In your bedroom, if you sleep with the door and windows closed, then the carbon dioxide can cause drowsiness, grogginess, and tiredness when you wake up in the morning (again depending on the size of your bedroom).

To improve the air circulation, you can consider placing a fan near a window. If you have plenty of money, you can consider getting a ventilation system installed professionally. If you have allergies, or if you want to stop the pollution in air, you could also get a HEPA air filtration system installed.

According to the American Society of Heating Refrigerating, and Air Conditioning Engineers (ASHRAE), it is recommended that ventilation be used to prevent the concentration of carbon dioxide in indoor air rising above approximately 1100 PPM (0.1%).

Unfortunately, even when a building has a ventilation system, the version of the ASHRAE ventilation standard from the year 2007 can result in indoor concentrations up to 2100 PPM above outdoor conditions. Concentrations in poorly ventilated spaces can be even higher (3000 to 4000 PPM), causing occupants to suffer drowsiness and lethargy.

Therefore, especially in older buildings and houses, even if a ventilation system is present, it may be inadequate, especially as the concentration of carbon dioxide in the outdoor air continues to rise every year.

Classrooms in schools often have bad ventilation or even no ventilation system at all. The amount of carbon dioxide rises quickly in a room containing 30 students. It is possible that the students begin to become drowsy and lethargic after as little as one hour, causing only the first hour of each day of school to be fully productive.

You can encourage your children to open windows in classrooms (do not rely on teachers to perform this essential task) and to sit near an open window.

The U.S. Centers for Disease Control and Prevention (CDC) recommend that school classrooms have a ventilation system that brings in 0.28 m³ (282 liters) of fresh air per minute per person. For 30 students, that is over 8 thousand liters per minute. That is a lot of air to move!

Do plants absorb carbon dioxide?

Deniers of global heating say that plants will absorb all of the carbon dioxide that humans produce from the burning of fossil fuels. However, they are ignoring the fact that plants release carbon dioxide during the night.

During photosynthesis (when a plant is receiving sunlight), a plant absorbs carbon dioxide, but how should a plant survive when its energy source (sunlight) disappears during the night? The answer is that plants reverse their cycle during the night. To generate energy and stay alive at night, plants break down the carbohydrates that they created during the daytime.

When a tree grows in size significantly, it can permanently store some carbon dioxide in its trunk, but not enough. Plants can absorb only half of the carbon dioxide produced by the burning of fossil fuels. Furthermore, it is not permanent storage, because the carbon dioxide is released again when the plant dies or if it is burned in a wildfire or deliberate deforestation.

In addition, rising temperatures make it difficult for plants to absorb carbon dioxide. Higher temperatures eventually lead to a water vapor pressure deficit. This means that hot weather increases the evaporation of water from the leaves of a plant, leading to insufficient hydration, leading to a degradation in the ability to absorb carbon dioxide.

Even if the plant does manage to absorb some carbon dioxide despite unusually hot or dry weather, the plant will release the carbon dioxide during the nighttime anyway.

The evidence of global heating is incontrovertible and obvious

The deniers of global heating are clearly delusional. With our own eyes, we can see that the global heating is really happening. For example, look at the massive shrinkage of glaciers around the world. The following photographs show the massive shrinkage of the Athabasca glacier in Canada:

The following photographs (by Christine Levy) show the shrinkage of the Morteratsch glacier in Switzerland:

The proof of global heating consists of thousands of examples. It is undeniable, incontrovertible, and indisputable. Nowadays only crackpots with a death-wish continue to deny the extensive evidence of global heating and climate change.

Collective action or collective suicide

Following, you can see the chart showing the ongoing increase in carbon dioxide in the air (as of September 2025). As you can see, it still looks as if nothing is being done to stop this disaster. In 2022, the United Nations secretary general António Guterres said:

“No nation is immune. Yet we continue to feed our fossil fuel addiction. We have a choice. Collective action or collective suicide. It is in our hands.”

So far, the chart still indicates that humanity has chosen collective suicide:

The survival of our world is at stake. It is very important that everybody stop voting for political parties that refuse or fail to stop the burning of fossil fuels as quickly as possible.

It is also important and necessary to build additional nuclear power stations. Solar panels and wind turbines are great inventions, but they alone are incapable of meeting the world's electricity and electrofuel requirements. They must be supplemented with nuclear power.

We have little time remaining. We definitely cannot afford to wait 100+ years until an alternative to nuclear power is possibly maybe invented (if ever). The world is already dangerously overdue in ending the burning of fossil fuels. We must act now.