The Hidden Problem with “Deep Breathing”: How Common Breathwork Practices Can Cause Hyperventilation

In the wellness world, we’re often told to “take a deep breath” to calm down, relax, or improve focus. Yoga classes, mindfulness apps, and fitness coaches alike emphasize deep breathing as the key to stress reduction and vitality.

But here’s the paradox:
Most people misunderstand what “deep breathing” actually means, and the way it’s commonly practiced can do the opposite of what it’s supposed to.

When we breathe too deeply or too frequently, we can unintentionally cause chronic or acute hyperventilation — leading to less oxygen delivery to our cells, not more.

Let’s unpack the biochemistry behind this, and how the Oxygen Advantage approach reframes the way we should be breathing for real performance and calm.

The Biochemistry of Breathing: Why Less Can Be More

Breathing serves two main biochemical purposes:

1. Oxygen (O₂) delivery to cells for energy production.

2. Carbon dioxide (CO₂) regulation, which controls blood pH, influences oxygen release, and affects nervous system balance.

We often think oxygen is the star of the show, but CO₂ plays an equally vital role in how efficiently oxygen is used by the body.

The Bohr Effect: How Oxygen Is Actually Delivered

In 1904, physiologist Christian Bohr described a critical relationship between carbon dioxide and oxygen delivery — now known as the Bohr Effect.

Here’s the simplified version:

• Hemoglobin in red blood cells carries oxygen.

• When CO₂ levels are normal, hemoglobin easily releases oxygen into tissues.

• But when CO₂ levels drop (as happens during heavy or deep over-breathing), hemoglobin holds onto oxygen more tightly.

So, paradoxically:

The more you breathe, the less oxygen your cells may actually receive.

This means that when we “deep breathe” in a way that lowers CO₂ too much, we can cause vasoconstriction (narrowing of blood vessels) and reduced oxygen delivery — particularly to the brain and muscles.

The Hyperventilation Trap

Hyperventilation simply means breathing more than your body’s metabolic needs require, not necessarily fast or panicked breathing, but excessive ventilation.

Even slow, big “deep breaths” can trigger mild hyperventilation if they lower CO₂ below optimal levels.

This can lead to:

• Lightheadedness or dizziness

• Tingling sensations in the fingers or lips

• Fatigue or brain fog

• Increased heart rate and anxiety

Ironically, people often interpret these sensations as needing more air — so they breathe even more deeply, worsening the cycle.

Oxygen Advantage: Redefining “Deep” Breathing

The Oxygen Advantage, developed by Patrick McKeown, teaches that functional breathing is about light, slow, and deep. Not big and loud.

Here’s the difference:

Misunderstood “Deep Breathing”Oxygen Advantage “Functional Breathing”Large-volume breathsLow-volume, gentle nasal breathingMouth breathing commonStrictly nasal breathingFocus on oxygen intakeFocus on CO₂ tolerance and balanceCan cause CO₂ dropMaintains or gently raises CO₂Can induce lightheadednessPromotes calm and alertness

In Oxygen Advantage, “deep” refers to breathing low into the diaphragm, not breathing a lot of air.
The goal is to breathe in a way that is:

• Quiet (no audible breathing)

• Slow (around 6–10 breaths per minute)

• Through the nose

• Controlled by the diaphragm

This optimizes the balance of oxygen and carbon dioxide, supports parasympathetic activation (the body’s rest-and-digest mode), and trains your body to become more tolerant of CO₂, improving endurance, focus, and resilience.

Why CO₂ Tolerance Is the Real Superpower

Instead of thinking of CO₂ as a “waste gas,” we can think of it as a key that unlocks oxygen delivery.
When we train to tolerate slightly higher CO₂ levels, for example, by breathing lighter or holding the breath briefly after exhale (as taught in the Oxygen Advantage method) we retrain the body to:

• Reduce over-breathing habits

• Improve blood flow to the brain and muscles

• Enhance endurance performance

• Calm the mind and reduce anxiety

In short, CO₂ tolerance equals oxygen efficiency.

The Takeaway

If you’ve ever practiced “deep breathing” and felt dizzy, fatigued, or oddly anxious — you may have been over-breathing.

True optimal breathing isn’t about taking in more air, but about using what you already have more efficiently.

As Patrick McKeown puts it:

“Breathe light to breathe right.”

So next time someone tells you to “take a deep breath,” remember:
Make it light, slow, and nasal, not big or forced.
Your body, and your brain, will thank you.

Sam Chidwick