Pack years is a measure of how much you have smoked in your life.
Despite what you might assume from the name, it is not the number of years you have smoked.
That’s just one part of the math used to count pack years.
Verywell / Joshua Seong
The other part is how much you’ve smoked each day during that time.
Researchers also use pack years as a standard way to measure data in studies on smoking and disease.
This article looks at how to count pack years and what the answers may mean for you.
In general, the more pack years you have smoked, the greater your risk of cancer.
If you were looking at a graph plotting data of the two, you’d see them rise together.
For example, female smokers appear to develop lung cancer afterfewerpack years than males.
The same study suggests the age someone starts smoking may play an important role as well.
Associating risk with pack years also ignores the fact thatlung cancer occurs in never-smokers.
Rather, it is how much they are currently smoking that seems to matter most.
That’s not the case for lung problems, though.
One study looked at lung function in more than 25,000 people.
Even former smokers showed lung damage that lasted for decades.
If you quit smoking, you have a good chance of lowering your risk of cardiac diseases.
That is something worth celebrating.
The effort to quit isalwaysworthwhile.
That said, your risk of lung damage including cancer won’t go away.
There was no “dramatic drop-off” after 15 years of quitting.
It is determined by multiplying the years you’ve smoked by the number of cigarettes per day.
Pack years matter when considering the health of both current and former smokers.
Otherwise, their recommendations are the same as the USPSTF’s.
Summary
Doctors often use pack years to estimate the risk of getting lung cancer.
While it will always help to quit, that won’t entirely erase the risk because of the smoking.
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American Cancer Society.Lung cancer risks for non-smokers.
