The recovery timeline
What happens when you quit smoking
The whole timeline in one table, followed by the part nobody includes: which of these milestones are load bearing and which are there to get you through a Tuesday.
Written by Lee H. Last reviewed 31 August 2026.
The eleven milestones, in order
This is the catalog the app itself ships, word for word. It is written once and pinned by a conformance test so the wording cannot drift between the iPhone, Android and desktop versions, which matters more for a health claim than for anything else in the app.
| After | What the timeline claims |
|---|---|
| 20 minutes | Heart rate and blood pressure drop. |
| 12 hours | Carbon monoxide in the blood returns to normal. |
| 24 hours | The risk of a heart attack begins to fall. |
| 48 hours | Nerve endings start to regrow, and smell and taste sharpen. |
| 2 weeks | Circulation improves and lung function increases. |
| 1 month | Coughing and breathlessness ease as the cilia in the lungs recover. |
| 1 year | Excess coronary heart disease risk is about half that of a smoker. |
| 2 years | Stroke risk can fall towards that of a non-smoker. |
| 5 years | Cancer risk of the mouth, throat, oesophagus and bladder is roughly halved. |
| 10 years | The lung cancer death rate is about half that of a continuing smoker. |
| 15 years | Coronary heart disease risk is close to that of a non-smoker. |
The first four are the weakest, and they are the ones everybody quotes
Twenty minutes, twelve hours, twenty-four hours, forty-eight hours. Every quit smoking article leads with these, and they are the least useful entries on the list.
"Heart rate and blood pressure drop" at twenty minutes is describing the end of one cigarette's effect. It happens twenty minutes after any cigarette, including one you smoked in the middle of a thirty year habit. It is the drug wearing off. The same goes, to a lesser degree, for carbon monoxide clearing at twelve hours.
That does not make them worthless. On day one you need something, and "your blood chemistry is already different" is true and is something. But a timeline that front-loads its most impressive-sounding entries and puts the ones that change your odds of dying at years seven through eleven is telling you about the wrong end of it.
Twenty minutes is the drug wearing off.
The four that actually change your odds
- 1 year: excess coronary heart disease risk about halved. The first entry about staying alive, and the biggest single step on the list. One year buys you half of the heart risk back.
- 5 years: several cancer risks roughly halved. Mouth, throat, oesophagus, bladder. Slower to arrive, and it keeps arriving.
- 10 years: lung cancer death rate about half a continuing smoker's. The one people are usually thinking about when they ask the question, and it is a decade out. There is no short version of this milestone.
- 15 years: coronary heart disease risk close to a non-smoker's. The furthest point the standard timeline goes, and note the word "close". Not equal.
Read those four together and the shape is obvious: the heart recovers a long way and the lungs recover more slowly and less completely. That asymmetry is why life expectancy models put a permanent floor under the loss.
Why the app makes you earn day one first
A small thing worth explaining, because it looks like a bug the first time you see it. The app will not show you the twenty minute milestone until you have logged one whole smoke-free day. Twelve hours and twenty-four hours also require that same first day.
It works in days, because a daily check-in is the only thing it actually knows. Awarding a twenty minute milestone to somebody who smoked an hour ago would be the app inventing a fact about them. So the early milestones all wait for the first clean day, and then arrive together.
Everything after that maps to the number you would expect: 14 days for the two week entry, 30 for one month, 365 for one year, and 5,475 for fifteen years.
What this timeline is, and what it is not
- It is a population summary. Every line is "on average, in studied populations". None of it is a statement about your lungs, your heart or your history, and none of it can be.
- The wording is deliberately hedged, and the hedges are real. "Begins to fall", "can fall towards", "roughly halved", "close to". Those words are doing work. A version of this timeline that removes them is a worse version.
- It stops at 15 years. Not because nothing happens afterwards, but because that is where the widely published timeline stops. Anything beyond it would be somebody's extrapolation.
- It is not the same thing as the years figure. The timeline is about risk of specific diseases. The life expectancy calculator is about years of life, built from a different body of research. They agree in shape and they are not the same measurement.
Nothing on this page diagnoses, treats or prevents any condition, and it gives no medical advice. It is a summary of a widely published recovery timeline, presented so you can go and read the source. No guarantee is made or offered about the accuracy of any figure or calculation on this site. Talk to a doctor or a quitline about stopping smoking. In the US, that is 1-800-QUIT-NOW.
Keep reading
Where to go next
I quit years ago, what did I get back?
The same clock, measured in years of life.
How many years do you get back?
The four published bands, and why the age you stop at decides most of it.
One year smoke free
Why the twelve month mark sits on the steepest part of the curve.
How the estimate works
Every source behind the numbers, and every place the model stops.
Sources
- US Department of Health and Human Services, The Health Consequences of Smoking: 50 Years of Progress. A Report of the Surgeon General, 2014. The standard recovery timeline summarised above draws on this body of work.
- Jha, P. et al., "21st-Century Hazards of Smoking and Benefits of Cessation in the United States", New England Journal of Medicine, 2013, for the years-of-life side of the picture.