Cigarette smoking is the number one risk factor for lung cancer, the second most common form of cancer and a leading cause of death worldwide. A 2017 study found that heavy smokers' lung cancer risk drops by nearly 40 percent just five years after quitting smoking,

The study involved more than 8,900 people enrolled in two large cohort studies. Researchers tracked the participants' health for an average of 30 years and determined their cancer risk based on whether they were current, former, or never smokers.

They found that current and former smokers had a higher risk of developing lung cancer than those who never smoked, but that risk increased tenfold if they were heavy smokers (defined as smoking one pack daily for 21 years or longer), with nearly 93 percent of lung cancers occurring in heavy smokers.

Five years after quitting, former heavy smokers saw a 39 percent reduction in their lung cancer risk compared to current smokers, and this risk continued to decrease over time. However, even 25 years after quitting, heavy smokers' risk of lung cancer was still more than three times higher than that of people who had never smoked.

These findings suggest that smoking, especially heavy smoking, markedly increases a person’s risk of developing lung cancer. And although quitting smoking reduces lung cancer risk, former smokers' risks remain higher than never smokers'.

Many harmful behaviors, such as smoking or overeating, are rooted in reward-based processes. Consequently, people often engage in these behaviors in response to triggers, such as emotional or mental stressors, or external prompts, such as advertising and social pressures. Cognitive behavioral approaches like mindfulness can help people who engage in harmful behaviors become more mindful of these triggers. In turn, they can reevaluate their habits and develop strategies that help them avoid engaging in harmful behaviors. Learn more in this clip featuring Dr. Ashley Mason.

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