Perhaps you have already taken a deep breath to calm yourself down. Quite intuitively, without giving it much thought. But have you ever asked yourself what your body actually needs at that moment?

When we think of breathing, most of us immediately think of oxygen, the "good gas" that brings life. And CO₂? It's often simply seen as something that has to go. A waste product.

But what if that wasn't the case? What if CO₂ wasn't just harmless, but actually crucial for your health, especially for your brain?

I'll show you five surprising facts about CO₂. And maybe you'll look at your breath with completely new eyes after reading them.

1. it's not a lack of oxygen, but CO₂ that tells your body to breathe

Do you know that feeling of breathlessness? Like you're not getting enough air? Most people think it's caused by a lack of oxygen.

But that's not true. It's not the lack of oxygen that triggers the breathlessness, but the rising CO₂ level in your blood. As soon as this level reaches a certain limit, your brain stem registers: time to breathe!

If you have a low CO₂ tolerance, you feel the stimulus more quickly - you start to breathe more shallowly, and often more quickly. This is exactly the pattern that occurs when you are stressed or anxious.

The good thing is that you can train it. The more you play with your breathing and breathe more consciously, the more your body gets used to CO₂. And you learn to stay calm, even when your CO₂ rises.

2. CO₂ brings the oxygen to where it is needed

You may have heard that oxygen is important for your energy. Of course it is! But did you know that without CO₂, the oxygen doesn't really get there?

Because CO₂ helps:

• keep the blood vessels open so that the oxygen-rich blood can flow properly

• the haemoglobin to release the oxygen again as soon as it reaches the cell (this is called the Bohr effect)

• protect the mitochondria, the power plants of your cells, from too much oxidative stress

Simply put: CO₂ acts like a delivery service that ensures that the valuable cargo, oxygen, arrives where it is needed. Without CO₂, the oxygen gets "stuck" in the blood.

3. too much oxygen can damage your brain

Yes, really. This realization surprised me myself.

As early as 1946, Kety and Schmidt showed in a study that inhaling pure oxygen reduces blood flow to the brain. Why? Because the blood vessels constrict when there is too little CO₂.

In comparison, breathing air with a little more CO₂ led to significantly better blood flow. The brain vessels widened and more oxygen actually arrived.

In other words, if you just make sure you breathe in as much oxygen as possible without paying attention to CO₂, the exact opposite of what you want will happen. Less reaches the brain, not more.

4. doctors use hyperventilation to "shrink" the brain

This sounds almost like science fiction, but it's reality.

During certain brain operations, doctors specifically use hyperventilation - rapid, deep breathing. This causes the CO₂ level in the blood to drop sharply. As a result, the blood vessels in the brain contract and the brain becomes smaller and firmer. This creates more space for surgery.

However, a study from 2019 criticizes this practice. Although it is widespread, there is a lack of good evidence of its benefits. The researchers call it a "double-edged sword".

In everyday life, this means that if you unconsciously hyperventilate frequently, e.g. during moments of stress, you are literally depriving your brain of oxygen - even though you think you are breathing "more".

5. conscious breathing could help your brain to tidy up

While you sleep, something fascinating happens in your brain. A cleansing system - called the glymphatic system - becomes active. It helps to remove waste products such as beta-amyloid, which are linked to diseases such as Alzheimer's.

Excitingly, studies show that CO₂ could also support this process during the day. Researchers discovered that rhythmically altered CO₂ levels stimulate the circulation of cerebrospinal fluid - similar to deep sleep.

What does this have to do with you? Practices such as slow diaphragmatic breathing, meditation, yoga or tai chi naturally change the CO₂ levels in your blood. This could help to "cleanse" your brain when you are awake.

Conclusion: your breath is much more powerful than you think

From breath stimulation to cell cleansing - CO₂ is not a waste product, but an important regulator for your body and your brain.

We must stop fearing CO₂. It's not about breathing in as much oxygen as possible. It's about balance. And it's about becoming more aware of your breathing again.

Perhaps you would like to simply observe how you breathe today - without changing anything. And feel what changes inside you.

Extra tip: Cardihaler for CO₂ tolerance

If you want to delve deeper into this topic and specifically train your CO₂ tolerance, theCardihaler can help you with this. With this portable breathing tool, which is suitable for everyday use, you can gently increase your tolerance to CO₂ and make your breathing more conscious in just a few minutes of breathing training.

Find out more here:Discover Cardihaler

Give it a try! Your body will thank you.