16/05/2026
Understanding CO2 Retention In COPD
A lot of people with COPD hear the words “CO2 retention” but don’t fully understand what it actually means, why it happens, or why it can make them feel so unwell.
So, let’s break it down a bit.
We breathe in oxygen, but we also need to breathe OUT carbon dioxide (CO2), which is a waste gas produced naturally by the body. Normally the lungs remove this CO2 through breathing.
However, with COPD and other lung conditions, the lungs may struggle to fully empty the air properly. Breathing can become shallow, restricted, fast or trapped in the lungs, causing stale air and excess CO2 to build up over time. This is what is known as CO2 retention.
Some people may experience symptoms such as increased breathlessness, fatigue, headaches, poor sleep, dizziness, anxiety, chest tightness, brain fog, confusion or feeling sleepy during the day.
There can be many things contributing to CO2 retention and breathing difficulties.
Breathing patterns play a huge part. Many people unknowingly begin breathing faster, shallower and more through the upper chest over time, especially during stress and anxiety. Mouth breathing, poor posture, lack of movement, weakened breathing muscles and air trapping can all contribute as well.
Food can also play a much bigger part than many people realise. High refined carbohydrates, processed foods, foods that increase inflammation or bloating, and eating in ways that place more pressure on the digestive system can all affect the breathing and the amount of pressure already being placed on the body.
Stress and anxiety are another big factor because when the body constantly stays in a tense, reactive or panic state, the breathing patterns often become even more inefficient and exhausting.
Certain medications can also affect CO2 levels in some people. Some drugs may affect the respiratory control centre in the brain and slow the breathing down, while others can affect the body’s acid-base balance and contribute to CO2 retention indirectly. Sedatives, opioids and medications that suppress breathing are well known for potentially causing respiratory depression and CO2 build-up. Certain medications such as corticosteroids and diuretics may also influence the body’s balance in ways that can contribute to increased CO2 retention in some people.
This is why I always say the body has to be looked at more broadly and not just through one symptom alone.
Most people naturally focus only on the lungs because the breathing is what they feel the most but often do not realise how much the rest of the body and lifestyle can also affect the breathing over time.
Stress, anxiety, poor sleep, inflammation, food choices, lack of movement, posture, breathing habits, smoking, medications, emotional pressure and daily lifestyle patterns can all place additional pressure on the body and lungs without people fully realising it.
The lungs are not working separately from the rest of the body. Everything connects, which is why becoming more self-aware and looking at the body more holistically becomes so important 😊
So how can we start helping support the body to help reduce CO2 retention?
When I first started my own Back to Breathing journey 6 years ago, I began realising that it wasn’t just my lungs affecting my breathing. Stress, inflammation, food, lifestyle habits, anxiety, poor breathing patterns and the overall pressure being placed on my body were all contributing as well.
The more self-aware I became, the more I started reconnecting the dots between the body, the mind and the breathing.
By becoming more self-aware of how we breathe during the day, slowing the breathing down gently, improving posture, reducing mouth breathing where possible, reducing stress and anxiety, supporting the body through better nutrition, gentle movement, better rest and learning how to calm the body instead of constantly staying in stress mode.
The goal is not to force the breathing, but to help support the body in ways that may allow the breathing to become calmer, more efficient and less exhausting over time.
Although all 6 elements should be worked on together, it is crucial to first begin understanding mindset and self-awareness, because once you start becoming more aware of your body, habits, emotions, breathing and daily patterns, the other 5 elements often become much easier to work on 😊
Let´s get Back to Breathing