The biggest impact smoking has on lungs is the damage done to the cilia. Cilia are tiny, hairlike protrusions in your lungs and respiratory tract that move back and forth as you breathe, to keep out foreign material or contagion. The images, taken by a scanning electron microscope, show cilia in healthy lungs. When you smoke, the cilia are destroyed, and you are unable to protect yourself against the contaminants and contagions you inhale. Cilia also help to move mucus through the lungs. Without cilia, many smokers develop a chronic cough, which is an attempt to move mucus from the lungs that the cilia would normally be moving.
After 72 Hours
If you smoke, there is good news. The human body is a healing machine. If you quit while you are healthy, your body can heal from most or all of the damage done by smoking. Within 72 hours of quitting, your lungs begin repairing themselves, and you will probably start breathing easier and better, as the bronchial tubes in your lungs begin to relax.
2 weeks to 9 months
Between 2 weeks and 3 months after quitting, your circulation improves, and your lung function increases by 30 per cent. Your lung function will continue to improve over 9 months as the cilia begin to regrow. By 9 months, smoking-related coughing, congestion and shortness of breath should slow and cease.
After 1 year
If you can quit for a year, your risk of coronary heart disease will drop to half what it was when you were smoking. After 5 years, your risk of stroke will go down to that of a nonsmoker. After 10 years, your risk of lung cancer will go down by half, and your risk of other smoking-related cancers, like those of the mouth, throat and oesophagus, will also decline.
Ways to speed recovery
During the first 9 months, a few strategies can help your lungs recover, especially as you begin to cough up mucus and material from your lungs. Eat right. Get adequate sleep and moderate exercise. Drink at least 1 litre of water a day to thin out the mucus. Using a facial steamer or breathing in a steamy shower will help. Boil a pot of water and place it on a table where you can sit with your head over it. Drape a towel over your head to breathe in the steam. Use a device such as PowerBreathe or the RespiVest (see Resources), to increase your lung performance, even if you have chronic obstructive pulmonary disease (COPD).
Smoking cessation programs are available to help you quit. Check out the QuitNet program directory in Resources for more information.