How old are your lungs?
The NHS concept that measures your real lung age — and the gap smoking has carved into it.
Your lungs are estimated to be 7 years older than your actual age. Lung function improvement begins within weeks of quitting.
Based on the concept popularized by NHS and Australian health agencies. After quitting, lung function can improve by up to 30% within 1 month, and lung aging slows significantly.
Your lungs can be older than you are.
Lung age was designed to make invisible damage visible — and it works.
Lung age is the idea that your lungs can be older than you are. Popularized by the NHS and Australian health agencies, it estimates how much of your lung function has been lost to smoking and expresses it as an age. A forty-year-old who has smoked a pack a day for twenty years might have the lungs of a fifty-five-year-old.
The calculator above uses a simple formula — chronological age plus a fraction of your pack-years — to give you a quick estimate. For a precise number, you would need a spirometry test at a clinic. But the estimate is good enough to make the damage visible, and that is the point: most people who see their real lung age make a different decision the next morning.
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