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What happens if I suddenly stop smoking?


Quitting smoking can be very difficult, both physically and mentally. Many smokers who have quit say it was one of the hardest things they have ever done. However, the health benefits of quitting are enormous. If you are considering quitting smoking, it is important to understand what happens to your body when you stop. Knowing what to expect can help motivate you to stop smoking and stick to it.

What happens in the first 20 minutes after you stop smoking?

Within 20 minutes of your last cigarette:

  • Your heart rate and blood pressure start to return to normal levels.
  • The temperature of your hands and feet increases as circulation improves.

Smoking causes immediate effects on your cardiovascular system. It causes your heart rate to spike and narrows your blood vessels, increasing blood pressure. Carbon monoxide in cigarette smoke prevents oxygen from being transported in your blood properly. Just 20 minutes after your last cigarette, these effects start reversing as your body begins healing.

What happens after 8 hours?

After 8 hours of no smoking:

  • Nicotine and carbon monoxide levels in your blood reduce by more than half.
  • Oxygen levels in your blood return to normal.
  • Your risk of heart attack also starts decreasing.

Nicotine from cigarettes leaves your blood very quickly. It has a half-life of only 2 hours, meaning half of the nicotine in your body will be gone after 2 hours. Carbon monoxide leaves even faster. After 8 hours of not smoking, your blood oxygen and carbon monoxide levels can return to normal. This starts reversing the risk of heart disease caused by smoking.

What happens after 48 hours?

Two days after quitting smoking:

  • Your nerve endings start to regrow.
  • Your senses of taste and smell may improve as nerves heal.
  • The nicotine withdrawal symptoms will be at their peak.

Smoking dulls your senses of taste and smell by damaging nerve endings and cells in your nose and mouth. After 48 hours of quitting, your nerve endings start to heal, allowing your senses to reawaken. However, this is also when nicotine withdrawal symptoms will be at their worst, including cravings, anxiety, irritability and depression. Power through the first few days by keeping yourself busy and distracting your mind from cigarettes.

What happens after 72 hours?

Three days after your last cigarette:

  • Your bronchial tubes relax and your lung capacity increases, making breathing easier.
  • Your lungs start to clear out mucus and debris.
  • Your energy levels and alertness may increase.

After three days without cigarettes, the nicotine has completely left your body. Your bronchial tubes start to relax and widen. This makes breathing easier and allows your lungs to get rid of mucus and start clearing out the buildup of tar and toxins from smoking. As your lung function improves, you may notice your energy levels and alertness increasing.

What happens after 2 to 12 weeks?

Two weeks to three months after quitting:

  • Your circulation and lung function continue improving.
  • You cough and wheeze less.
  • You may be less at risk for colds and infections as your immune system strengthens.
  • Exercise becomes easier as you have less shortness of breath.

As more time passes without smoking, your lungs and circulation keep improving. Coughing, wheezing and shortness of breath will continue diminishing, making day-to-day physical activities much easier. Your immune system recovers from the damage smoking did to it, making you less prone to infections. The cilia (tiny hair-like structures) in your airways that help clear mucus and debris also start to regain normal function.

What happens after 3 months?

After three months smoke-free:

  • Your lung function can increase up to 30%.
  • Blood circulation continues improving.
  • Exercise is becoming significantly easier.
  • Your risk of heart attack has dropped significantly compared to when you were smoking.

Three months after quitting smoking, your lung capacity can increase by nearly a third. This helps reduce coughing and shortness of breath. Blood circulation also continues improving, reducing your risk for cardiovascular diseases like stroke and heart attack. At this point, moderate physical activity should not leave you out of breath. You’ll also notice that your immune system is likely stronger, warding off colds more easily.

What happens after 1 year?

One year after quitting:

  • Your excess risk of coronary heart disease is half that of a smoker’s.
  • Your lung cancer death rate is about half that of a smoker’s.
  • Your risk of stroke is reduced to the same as a nonsmoker’s.
  • The cilia in your airways have fully regrown, improving lung function.

After a year without cigarettes, your risk for smoking-related heart disease and lung cancer have dropped by half compared to if you had continued smoking. With the regrowth of cilia in your lungs, your risk of infection is now very low. At this milestone, your lung function can increase to up to 90% or more of what it would have been if you had never smoked at all. You will notice that most smoking-related symptoms like coughing and shortness of breath are mostly gone. Your significantly reduced risk of stroke and improved artery function also lower your risk for conditions like vascular dementia.

What happens after 5 years?

Five years after quitting smoking:

  • Your risk of mouth, throat, esophagus and bladder cancers is half that of a smoker’s.
  • Your stroke risk is now equal to that of a nonsmoker.
  • Your risk of dying from lung cancer is between 30-50% of a smoker’s.
  • Your risk of coronary heart disease is now equal to a nonsmoker’s.

After 5 years without smoking, your body’s healing has come along even further. Your risk of developing smoking-related cancers of the mouth, throat, esophagus and bladder are now half that of a smoker’s. Your arteries have become much cleaner, reducing your risk of stroke and heart attack to the same level as someone who has never smoked. Your risk of dying from lung cancer is also now between 30-50% compared to if you had continued smoking.

What happens after 10 years?

Ten years after your last cigarette:

  • Your lung cancer death rate is similar to that of a nonsmoker.
  • Your risk of other cancers has declined significantly but is still higher than a nonsmoker’s.
  • Your risk of coronary heart disease is not very different from someone who never smoked.

A decade after quitting smoking, your lung cancer risk is very close to the same as someone who never smoked at all. Your likelihood of developing smoking-related cancers has declined dramatically compared to when you were smoking. The clean-up in your arteries means your risk of heart disease is highly reduced compared to that of either a smoker or a nonsmoker. However, it will still be slightly higher than someone who never smoked.

Conclusion

As the timeline shows, most of the healing process when you stop smoking occurs in the first year. But the beneficial effects continue for at least a decade after you quit. Your lungs and overall health continue improving as your body’s systems recover. The key is staying smoke-free and allowing your body’s natural repair processes to take place.

While quitting smoking is very difficult, your health improves in nearly every way when you stop. If you can get through the initial hurdle of nicotine withdrawal, the benefits start quickly and continue mounting over time. Keep your eyes on the many health improvements you have to gain by quitting. Stay motivated to kick your cigarette addiction once and for all and start reversing the damage smoking has done.

Time after quitting Healing effects
20 minutes Heart rate and blood pressure start to return to normal
8 hours Oxygen and carbon monoxide blood levels return to normal
48 hours Nerve endings begin healing, improving taste and smell
72 hours Bronchial tubes relax, making breathing easier
2 weeks to 3 months Circulation and lung function improve
3 months Lung function increases up to 30%
1 year Excess risk of heart disease is half of a smoker’s
5 years Risk of cancers is significantly lower
10 years Lung cancer death rate is close to a nonsmoker’s

The timeline above summarizes the many health improvements that take place when you quit smoking, from 20 minutes all the way up to 10 years smoke-free. The healing process starts quickly and continues gradually over time. Staying focused on these benefits can help inspire you to quit smoking and stick with being smoke-free.