How quickly do lungs recover?

When long-time smokers quit, do their lungs eventually restore themselves to normal condition? If they do, how many years does it ordinarily take?
Thanks very much.

There is a list somewhere that spells all that out by length of time. It might be in the AS3 FAQ.

It's all approximate but is a good guide.

7 years is about right. I heard 10 somewhere. Close enough.

It's always a benefit for the lungs to quit smoking at any time, at any age even if you've already been diagnosed with a lung disease. Emphysema can be slowed down drastically.

I've heard that if you quit smoking before age 35, you avoid
95% of the permanent damage smoking can do.

would it not depend on the amount of damage? I would think many a lung will NEVER recover.

What I've heard is that if you 1) quit before you are 35, 2)
quit before you rack up 20 pack-years (1 pack per day for 20 years,
2 packs per day for 10 years, etc.), and 3) you stay quit, you've avoided nearly all the increased risk.

I was told when I had my lungs imaged last year that it takes 7 years of not smoking for your body to return to its "non-smoker" state.

I know of three things you have to consider. First is your "risk factor" of smoking related disease. After having quit smoking, your risk of heart attack, lung cancer, etc., decrease substantially over the years. The second part of the answer has to do with what heals and what doesn't. If you have emphysema, for example, quitting smoking won't make you better, but it may slow or stop the progression of the disease. Quitting smoking won't stop cancer, I don't think. Then there is the matter of what does improve. I know that smokers hack goes away, and that your lungs grow back those little hairs that help keep them clean. Respiration slows, circulation improves, and in every way you become better athletetically.

I can't lay out a timeline for healing, but the question you asked is pretty deep and I thought I'd add some perspective.

Your elevated risk of heart disease drops to zero in a matter of hours or days.

Lung cancer, emphysema takes years for the risk to decline to the equivalent of a nonsmoker.

Heart disease is far more common than cancer, so take solace that the worse threat is taken care of promptly.