Quick answer: When you quit smoking, your heart rate and blood pressure drop within 20 minutes, and carbon monoxide in your blood returns to normal within 12 hours. Over the next weeks and years, lung function improves, your risk of heart disease falls by half at one year, and your risk of stroke and several cancers keeps declining.
Knowing what's happening inside your body is one of the best ways to stay motivated, especially on the hard days. Here's what to expect, hour by hour and year by year, based on data from the National Cancer Institute's Smokefree.gov and the American Cancer Society.
20 minutes after quitting
Your heart rate and blood pressure, which spike with every cigarette, start dropping back toward normal.
12 hours after quitting
The carbon monoxide level in your blood drops to normal. Carbon monoxide crowds oxygen out of your blood, so once it clears, your blood carries oxygen to your organs more efficiently.
1 to 3 days after quitting
Nicotine leaves your body within about three days. This is also when withdrawal usually hits hardest: cravings, anxiety, irritability and trouble concentrating tend to peak during the first 3 days. Many people also notice their sense of taste and smell starting to sharpen.
The good news is that symptoms usually ease over the first month. The first week is when slips are most likely, so plan ahead for your triggers and consider FDA-approved quit medications, which can make withdrawal more manageable.
2 weeks to 3 months after quitting
Circulation and lung function improve, and your risk of a heart attack begins to drop. Climbing stairs or walking briskly leaves you less winded, and the typical morning smoker's cough starts to fade.
Why you might cough more at first: Some people notice a wet, productive cough in the first weeks after quitting. This is usually temporary and a sign your lungs are healing. Smoking damages the cilia, the tiny hairlike structures that sweep mucus and debris out of your airways. As they recover, your lungs start clearing out what built up while you smoked.
See a doctor if you cough up blood, have a fever, or your shortness of breath gets worse instead of better.
1 to 9 months after quitting
Coughing, congestion, fatigue and shortness of breath keep decreasing. As your cilia regain normal function, your lungs get better at clearing mucus, which helps lower your risk of infections.
This is a good time to get a pulmonary function test and compare the results with your baseline.
1 year after quitting
Your risk of coronary heart disease is half that of someone who still smokes.
2 to 5 years after quitting
Your risk of stroke can drop to that of a nonsmoker. Your risk of cancers of the mouth, throat, esophagus and bladder is cut in half.
10 years after quitting
You're half as likely to die from lung cancer as someone who still smokes, and your risk of kidney and pancreatic cancer decreases.
15 years after quitting
Your risk of coronary heart disease is the same as that of someone who never smoked.
How do you know how your lungs are recovering?
How you feel gives you a general idea, but a pulmonary function test (spirometry) gives you real numbers. It measures how much air your lungs can hold and how fast you can move it in and out, so you can track your progress at each stage of your smoke-free journey.
[Book your pulmonary function test] and get a clear, measurable picture of how your lungs are healing.
Need help staying quit? Call 1-800-QUIT-NOW for free coaching, or visit Smokefree.gov.
FAQ (add to the post + FAQPage schema)
How long does it take for your lungs to heal after you quit smoking? Lung function starts improving within 2 weeks to 3 months. Coughing and shortness of breath keep decreasing for up to 9 months as the cilia in your airways recover. Some long-term damage may not fully reverse, which is why a pulmonary function test is useful for tracking your progress.
How long does nicotine withdrawal last? Withdrawal symptoms usually peak in the first 3 days and ease over the first month. Some people have cravings or mood changes for several months.
Is it normal to cough more after quitting smoking? Yes. A temporary wet cough is common as your cilia recover and your lungs clear built-up mucus. See a doctor if you cough up blood, have a fever, or your breathing gets worse.
What happens 1 week after you quit smoking? By one week, nicotine has left your body and the worst withdrawal symptoms are usually starting to ease. Taste and smell are often noticeably better. The first week is also when relapse risk is highest, so having a plan matters.
Is it too late to quit smoking after many years? No. Quitting benefits your health at any age, no matter how long or how much you've smoked. People who quit can add as much as 10 years to their life expectancy compared with those who keep smoking.
How can I measure my lung health after quitting? A pulmonary function test, such as spirometry, measures how much air your lungs hold and how quickly you can exhale. Repeating it over time shows how your breathing capacity is changing.
