What really happens when you quit smoking

For many smokers, quitting does not begin with a carefully planned date or a dramatic promise that this cigarette will be the last. Sometimes, it starts because the device is in the car and getting it feels like too much effort. Sometimes, it comes after years of knowing you want to stop. And sometimes, quitting cigarettes does not mean quitting nicotine at all. For Layla, the decision came after years of smoking had begun to affect even the most basic parts of her life. “I started smoking when I was 16,” she said. “I was actually really against smoking at first.” As more people around her began smoking, she eventually tried it herself. Cigarettes became vaping, then cigarettes again, and later IQOS. She found the heated tobacco product so unsatisfying that her consumption eventually reached around two and a half packs a day. By January, she was repeatedly developing lung infections and severe coughs. Eventually, breathing itself became difficult. “I literally couldn’t breathe properly. I was constantly coughing and wheezing,” she said. “I couldn’t run. I couldn’t even go up stairs without struggling.”  A friend had repeatedly encouraged her to stop before eventually telling her: “I’m just going to stop trying to convince you. When you decide you want to, you will.” Then, unexpectedly, she did. One day, Layla’s IQOS was sitting in her car. She decided to see whether she could leave it there for a day. “One day turned into two days. Then I thought, ‘Okay, maybe I can do three.’ Three days turned into a week, and I just kept going.” Seven or eight months later, she still has not gone back to smoking.

Quitting smoking does not always mean quitting nicotine

Dani had been smoking since he was 14 and said quitting had been somewhere in the back of his mind for years. “No one who smokes says they don’t want to quit,” he said. Smoking had begun interfering with his physical stamina, particularly when running. At the time of the interview, he had gone approximately 13 months without smoking and said he could now climb around five floors without becoming exhausted. But like Layla, stopping smoking did not immediately mean eliminating nicotine. Dani said the nicotine craving and feeling that he needed to smoke remained difficult to suppress. After initially trying to stop without a replacement, he began using nicotine pouches and later gum. Layla also initially attempted to quit cold turkey but quickly realized it was not sustainable for her. “I don’t think I would have been able to keep going that way, especially considering how much I used to smoke,” she said. “I needed something to help with the nicotine cravings.” She began using four-milligram nicotine gum before moving down to two milligrams. She now typically chews two pieces per day and plans to eventually stop using it completely.

Why is nicotine so difficult to leave behind?

Dr. Salah Zeineddine, a pulmonologist at the American University of Beirut Medical Center and Chief Medical Officer, explained that nicotine is responsible for the addictive pull of smoking. “The nicotine by itself is the addictive material,” he said, explaining that while tobacco smoke contains numerous other harmful substances, nicotine is what makes stopping so difficult. According to Dr. Zeineddine, there is no single cessation method that works for everyone. “Some people will use some nicotine replacement, whether gum or patch. Some people will use medications. Some people will just stop cold turkey, depending on the person.” For Layla and Dani, nicotine replacement allowed them to stop smoking while dealing with the dependence more gradually.

What actually happens to your lungs after you stop?

Dr. Zeineddine explained that smoking-related injury is cumulative. The consequences depend on how long someone has smoked, how much they smoke each day and their genetic susceptibility. For people who have developed emphysema or chronic obstructive pulmonary disease, some loss of lung function cannot be reversed. “What you lost is lost,” Dr. Zeineddine said. “But you can stop the rate of decline.” Everyone naturally loses some lung function with age, but smokers with emphysema or COPD can experience a much faster decline. Once they stop smoking, that accelerated loss can return toward the rate seen in a nonsmoker. The cardiovascular system also begins recovering, Dr. Zeineddine said the blood vessels and heart begin healing within around three months. Cancer risk takes considerably longer to fall. The risk begins declining within months, but someone who smoked for only a few years may take roughly three to five years to approach the risk of someone who never smoked, while a person who smoked for 15 or 20 years may need around 15 years.

“There’s nothing called a smoker’s cough”

One symptom Dr. Zeineddine believes should never be dismissed is a persistent cough. “There’s nothing called a smoker cough,” he said. “If you have a smoker cough, that means your lungs started suffering.” He identified recurrent unexplained coughing, persistent phlegm, shortness of breath during activity and coughing up blood as warning signs that should prompt someone to see a pulmonologist. For Layla, coughing, wheezing and breathlessness had become normal. Months after quitting, those symptoms have become far less frequent. “Sometimes I still feel like I can’t breathe properly, but it happens much, much less than it did before,” she said. She can now climb multiple flights of stairs without becoming extremely tired. Dani described a similar improvement. Dr. Zeineddine said former smokers often report having more energy, exercising more and becoming more active, sometimes within weeks of stopping.

Is switching to IQOS or vaping enough?

Dr. Zeineddine does not consider switching products equivalent to eliminating the health risks. Discussing IQOS, he said it may be less injurious to the lungs in some respects, noting that some people report coughing less after switching. However, he said it still carries risks involving cancer, blood vessels and the heart. He was particularly critical of vaping and e-cigarettes, describing them as extremely harmful. Layla’s experience also shows why switching products does not necessarily mean smoking less. IQOS did not satisfy her cravings enough, and her consumption eventually reached around two and a half packs a day.

Quitting rarely looks the same for everyone

Dani had thought about quitting long before he finally did. Layla began almost accidentally, leaving her IQOS in the car and challenging herself to make it through one day. Both continued using nicotine after they stopped smoking. Dr. Zeineddine emphasized that cessation aids can support quitting, but the decision itself remains central. “It’s an addiction,” he said. “You cannot stop somebody if they don’t work for it themselves.” For Layla, that echoed what her friend had told her: nobody else could make the decision for her. The first day without smoking did not become seven or eight months because she suddenly stopped craving nicotine. She still uses gum and is gradually reducing it. Her breathing has improved considerably, but quitting remains a process rather than a single event. One day became two, two became three, three became a week. Eventually, smoking stopped being something she was trying to quit and became something she no longer did.