If you are a smoker, you have surely heard that smoking damages your lungs. More surprisingly, without even killing the cells, the smoke does damage to the tiny hair-like extensions on the surface of your cells called cilia.
You may have known about the presence of cilia in the body, but why is it important to keep them in good shape?
Cilia are found in many parts of the body, notably the respiratory system. The cilia we find here are motile, which means they can move (non-motile cilia also exist). They coat the nasal passageways all the way down to where the trachea (the windpipe) first branches off into the lungs as air passages called bronchi.
The most crucial function they carry out in the respiratory system is to protect the passageways and to beat in a rhythmic manner to keep the airways clear of mucus and dirt. (See video below showing live beating of the cilia, from the Cilia Scientist)
Interestingly enough, in the nasal cavity, the cilia beat so that the particles move backwards towards the pharynx (the back of the throat), while in the trachea, the cilia beat upward towards the pharynx! This is so the mucus and dust mix can then be swallowed or, less politely, coughed up.
One way to damage the cilia is, of course, by smoking cigarettes. In fact, some of the thousands of chemicals in the smoke are actually toxic to cilia; resulting in their paralysis. This means the damaged cells are unable to clear the tar and mucus from your lungs, letting the tar get even deeper in your airways to cause inflammation and other possible complications.
Fun fact: “smoker’s cough” is more prevalent in the morning. The reason for this is because at night, the cilia’s clearing function is no longer inhibited by the smoke and can regain some function. Upon waking up, the smoker coughs to get the mucus and tar accumulation out of their lungs.
So why is this important?
Defective cilia, due to mutations or human behaviour, have a huge impact on the functioning of your body. At the end of the day, take care of your cilia and they will take care of you!
– Celia Dossot
Further studies if interested; smoking’s association with shortened cilia, effects of passive smoking on sinus cilia regeneration and cilia’s relationship with automated cell death.