The purpose of our respiratory system is to supply oxygen to our bodies and expel carbon dioxide. We all understand that and we notice pretty quickly when it’s not going well – shortness of breath, struggling to exhale, coughing, tiredness, lack of sleep and/or continual waking are some of the symptoms.
Like many human systems, when you examine what happens within the respiratory system, it’s astoundingly complex.
The lungs are one of our largest organs. The surface area of both lungs is roughly the size of a tennis court. On top of that, the total length of the airways running through them is 2,400 kilometres – that’s longer than the length of New Zealand!
Our lung capacity depends on our gender, size, age and health – an average male's lungs can hold 6L of air.
Every day we breathe in enough air to fill up a decent sized swimming pool – that’s every single day!
Now stop for a moment and think of that air going through your nose and mouth, through your bronchial tubes and into your lungs – think of that swimming pool’s worth of air and then think about what else is in that air.
We breathe in oxygen and other gases, particles of chemicals and matter - like burnt rubber from car tyres, we breathe in steams and vapours, we breathe in viruses, dust mites, fungal spores, bacteria and protozoa and occasionally we breath in a fly (or two), especially if we live in Queensland as I did for a while!
Our lungs and bronchial tubes are lined with a layer of cells called the respiratory epithelium. These surface cells have a big job as our first line of defence against the pathogens and foreign particles we breathe in such large quantities.
When these cells come into contact with invaders, they secrete substances such as mucins, defensins, lysozyme, lactoferrin and nitric oxide. These substances non-specifically shield the respiratory tract from the invader.
The epithelial cells also produce mediators such as reactive oxygen radicals, cytokines (TNF-α, IL-1β, granulocyte/macrophage colony-stimulating factor [GM-CSF]), and platelet-activating factor which drive inflammatory cells to the site of invasion.
Many of the lungs' epithelial cells have cilia, tiny hair-like structures that help to move mucus and debris out of our respiratory system - these can be damaged in diseases like COPD, so help is needed in moving irritants out of the lungs.
Our respiratory system is like a well managed orchestra, keeping the beat at the macro level, providing oxygen to our bodies, while operating at a granular level, managing cell signals and removing invaders.
And like the rest of us, our lungs age over time – this is seen in:
- Alveoli (in the diagram below, these are tiny air sacs at the end of the bronchioles where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out) which can lose their shape and become baggy;
- The diaphragm can become weaker, decreasing our ability to inhale and exhale;
- Ribcage bones become thinner and change shape, altering the ribcage so that it is less able to expand and contract with breathing;
- Nerves in the airways which trigger coughing become less sensitive to foreign particles meaning the particles build up in the lungs and can damage the tissue;
- Our immune system can weaken, leaving us more vulnerable to infections like influenza and pneumonia.
To help slow down the lung aging process it’s important that we:
- Breathe in clean air, indoor and outdoor - trying to reduce things like household cleaning chemicals and exposure to pollution;
- Exercise often to build the lungs and heart (which are muscles), even if it’s just gently – a walk or yoga is fantastic;
- Eat lung-healthy foods and beverages such as fresh fruit and vegetables and catechin rich green teas.
And just to finish – your lungs are your only organs which can float on water and crazily enough, some people can hold their breath for 20 minutes – I kid you not!
To read more about lung health and lung diseases, read some of our previous blogs:
Please contact us if you have any queries firstname.lastname@example.org and don’t forget to check out our new Zestt Wellness lozenge range and Breathe Easy!