One Cigarette Can Take 20 Minutes Off Your Life, Study Suggests

Smoking just one cigarette can reduce life expectancy by about 20 minutes, according to research commissioned by the U.K. government.

By quitting for a week, smokers can theoretically claw back an entire day of life expectancy, assuming they smoke 10 cigarettes a day. If a smoker quits on Jan 1 and sticks it out for a year, they’ll have bought back 50 days of life expectancy.

Cigarette smoking has fallen in popularity enormously in the U.S. in recent decades, particularly among young people. But 11.6% of the country’s adults still smoke, as do 3.8% of U.S. youth, according to the American Lung Association.

Quit Cigarette Smoking For New Year’s, Scientists Say

The study’s researchers urged members of the public to consider giving up smoking, which is a leading cause of preventable death, as a New Year’s resolution for 2025. The habit is linked to numerous serious health problems, from high blood pressure and heart disease to lung cancer, breathing problems and stroke.

Cigarette smoking is still thought to take the lives of hundreds of thousands of Americans every year. Around 16 million people in the U.S. are thought to have at least one disease caused by smoking.

“It is vital that people understand just how harmful smoking is and how much quitting can improve their health and life expectancy,” said Sarah Jackson, principal research fellow in University College London’s Alcohol and Tobacco Research Group. “The sooner a person stops smoking, the longer they live. Quitting at any age substantially improves health and the benefits start almost immediately.”

British TV doctor NHS Sarah Jarvis, who was not involved in the research, added: “As a GP, I see firsthand the devastating effects smoking can have on health.”

Beyond shortening lifespan, the habit worsens quality of life. “Each cigarette… also significantly increases the risk of many health conditions including heart disease, stroke, type 2 diabetes, dementia and chronic obstructive pulmonary disease.”

Studying The Impact of Each Cigarette

Jackson and other scientists at UCL used data from two decades-long U.K. population studies to work out their findings: the British Doctors Study and the Million Women Study.

The Doctors study has been monitoring the impact of cigarette smoking on thousands of doctors since it was launched in 1951. The Million Women Study has been tracking several health outcomes for 1.3 million U.K. women in the U.K. recruited between 1996 and 2001.

They worked out the average impact of smoking, per cigarette, based on the collated data.

“Minutes-off-life” is a relatively crude measure that doesn’t take into account the cumulative effect of smoking over time. Nonetheless, the results are still a stark reminder of the serious impact of smoking on many areas of health.

Indeed, the study shows a much stronger impact on life expectancy than previous research. A 2000 study published in the British Medical Journal found each cigarette took an average of 11 minutes of a person’s life expectancy.

How To Quit Smoking Cigarettes

Jackson said a range of tools were available to help smokers cut down and ultimately quit cigarettes. In the U.K., where the study was based, public health services provide dedicated “stop smoking” services, and provide nicotine replacement products.

In the U.S., resources including counselling and advice via phone, SMS and online are available through the Centers for Disease Control and Prevention.

Nicotine replacement products like gum, lozenges and patches are available over-the-counter, while inhalers and nasal sprays can be prescribed. These provide nicotine to ease withdrawal symptoms and help smokers quit cigarettes, which are much more dangerous.