How Much Can You Repair the Damage from Smoking After Quitting?

If you are among the nearly 56 million Americans who have quit smoking, congratulations are in order. A host of health benefits are on the way, and some begin to appear within minutes.

In the long run, however, the picture is much more complex. Some of the damage caused by smoking only fades after decades, and there is lung damage that cannot be repaired. In addition, the increased risk of developing lung cancer does not disappear completely.

Still, there are quite a few steps that former smokers can take to maximize the benefits of quitting, from changing their diet to increasing physical activity. Even if it is not possible to return the lungs to their original state, doctors emphasize that quitting smoking is still important, both for health and for quality of life.

"Quitting smoking is undoubtedly one of the most significant things a person can do for their health, at any age and at any stage," says Dr. Aric Singhi, an oncologist specializing in thoracic tumors at the MD Anderson Cancer Center in Houston.

Immediate benefits

According to an analysis by the American Lung Association based on federal health data, the number of former smokers in the US is currently twice the number of smokers, which stands at about 27 million. However, there is no simple answer to the question of how much the body is able to recover after quitting smoking. It depends on the number of cigarettes a person smoked, the length of time they smoked, and the organs that were damaged.

As a general rule, medical screening guidelines indicate that the greater the volume of smoking, the greater the risk. However, "there is really no safe level of smoking," says Singhi. "Even occasional or social smoking increases the risk of lung cancer and lung damage compared to a person who has never smoked."

Still, everyone who quits smoking begins to enjoy the benefits almost immediately. According to the American Lung Association, within about 20 minutes of quitting smoking, the heart rate may return to a normal level, even if the cessation is temporary. Within a few hours, the level of carbon monoxide in the blood also drops.

As people continue to abstain from smoking, the benefits grow. Within a few weeks, the cilia, tiny structures that remove mucus from the lungs, return to work and cause a cough that helps clean the lungs. Within a few weeks of quitting smoking, there is also some improvement in lung function, with a decrease in swelling and inflammation.

The risk of heart disease drops rapidly within the first few weeks and months after quitting smoking, says Dr. David Hill, a pulmonologist and chairman of the board of the American Lung Association.

"We don't tend to think of smoking as a systemic disease, but it is," he says.

Just quit

Melissa Reeves quit smoking more than a year ago, after smoking a pack of cigarettes a day, and has since enjoyed a series of improvements. Her senses of taste and smell have improved, and she is less out of breath during walks with her grandchildren.

"There is no doubt that something in the body is undergoing a healing process," says 65-year-old Reeves from Danville, Indiana.

However, some health improvements take time. According to Aruni Bhatnagar, a professor at the University of Louisville School of Medicine who studies the effects of tobacco use, smoking causes the accumulation of plaque on the walls of the arteries, and the process of clearing it can take 20 to 30 years.

Positive steps

In the long run, adopting a healthy lifestyle is a vital component in repairing the damage caused to the lungs. A 2022 study, in which more than 150,000 former smokers participated, compared those who followed recommendations for maintaining a healthy body weight, regular physical activity, a healthy diet, and limiting alcohol consumption with those who did not.

The study, published in the journal JAMA Network Open, found that among those who followed the recommendations most closely, the risk of death from any cause was 27% lower compared to those who did not follow them.

Regular physical activity, such as running or walking, strengthens the heart and reduces the risk of death from cardiovascular disease. It also strengthens the respiratory muscles, without which the lungs cannot function, and according to doctors, helps reduce symptoms associated with smoking, such as shortness of breath. In addition, it may slow the decline in lung function.

Physical activity also increases the activity of antioxidant enzymes in the body, which help protect cells from damage. According to Dr. Augustine Lee, a pulmonologist at the Mayo Clinic in Jacksonville, Florida, a lifestyle and diet that encourage the accumulation of antioxidants in the body are associated with a decrease in the risk of heart disease and cancer. Foods rich in antioxidants include dark green vegetables, blueberries, nuts, green tea, and fish.

In addition, drinking enough water helps flush toxins from the body, maintains optimal organ function, and thins mucus, making it easier for the lungs to stay clean.

"The combination of quitting smoking, physical activity, and a healthy diet all contribute to an improvement in lung function," says Lee.

According to doctors, there are several more steps that former smokers can take to reduce the risk of serious health problems and help their bodies recover. They should avoid exposure to secondhand smoke and check their homes for the presence of radon gas. "Many people do not know that radon gas is the second most common cause of lung cancer in the US," says Singhi.

Doctors also recommend that former smokers not switch to vaping instead of smoking. "The only thing that should enter the lungs is clean air," says Hill. "Vaping and e-cigarettes may have been marketed as less harmful, but we don't have data to prove that."

Close monitoring

However, it is important for former smokers to also understand the limitations of the recovery process. Although the lungs are able to clear the remnants of smoking after quitting, there is one key component that does not recover. Smoke destroys the alveoli, the tiny air sacs that allow the body to absorb oxygen and expel carbon dioxide. When too many alveoli are destroyed, an irreversible disease such as emphysema can develop, making breathing difficult.

"When the airways are scarred, there is no way to return the situation to its previous state," says Lee.

Smoking also doubles the natural rate of decline in lung function. "Even years after quitting smoking, one can suffer from shortness of breath and coughing, simply because of the natural decline in lung function," says Lee.

In addition, the toxic substances in smoke damage the DNA of lung cells, which serves as a kind of instruction book dictating how cells should act. Some of the damaged cells die, but those that survive can cause abnormal cell growth, i.e., cancer.

"According to the data we have, even decades after a person quits smoking, their risk can still be almost three to four times higher than that of a person who has never smoked," says Singhi.

Doctors also see preventive medicine as a key component in maintaining longevity. Singhi recommends that former heavy smokers undergo annual screening tests for lung cancer. Health insurance may cover the tests for those who have smoked an average of a pack of cigarettes a day or more for years.

"Screening tests are what allow us to detect lung cancer at an early stage, when it is best treatable," he says.

Former smokers should also see a doctor if they suffer from shortness of breath or a cough that lasts more than three months. These may be early signs of a disease such as chronic obstructive pulmonary disease. Although there is no cure for it, it can be managed, especially if treatment is started at an early stage.

Even if it is not possible to erase all the damage from smoking, those who have quit smoking can add healthy years to the end of their lives, which may be just as important to them as the length of their lives.

Patients sometimes tell Lee that they enjoy smoking and intend to continue until the day they die. The problem, according to him, is that smokers usually do not die quickly.

They may develop chronic obstructive pulmonary disease, such as emphysema, and require oxygen tanks regularly as their health condition deteriorates.

"You can't walk, leave the house, and any minor cold can turn into a serious incident that could lead to respiratory failure," he says. "It can be a difficult death."

This article was translated by Globes exclusively from The Wall Street Journal. Link to the original article in English.