There are a lot more factors involved besides just age, such as:
Were you exposed to second hand smoke growing up?
How old were you when you started smoking?
How much do you smoke?
How much smoke do you take in with each drag, and how deeply do you inhale?
Do you also smoke other things? (new studies show marijuana is harder on the lungs than tobacco).
Hopefully, you are asking because you have quit smoking, and just want to know if your lungs will return to normal. If you are asking because you are still smoking, and just want to know when you should count on having to quit, you are making the same mistake I made. and I have a clear plastic tube following me around the house now.
(Sorry if this sounds harsh or unsociable, but I am 52, have emphysema, and am still trying to get smoke free - as of this post, I have been smoke free for 26 hours).
This site complies with the HONcode standard for trustworthy health information.
The Content on this Site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease; or a recommendation for a specific test, doctor, care provider, procedure, treatment plan, product, or course of action. Med Help International, Inc. is not a medical or healthcare provider and your use of this Site does not create a doctor / patient relationship. We disclaim all responsibility for the professional qualifications and licensing of, and services provided by, any physician or other health providers posting on or otherwise referred to on this Site and/or any Third Party Site. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. We offer this Site AS IS and without any warranties. By using this Site you agree to the following Terms and Conditions. If you think you may have a medical emergency, call your physician or 911 immediately.