If you’re a smoker, you know that the habit is bad for you, and that quitting can improve your health and your longevity. If you’ve tried to stop smoking, you also know how tough that can be. Well, you might find just the motivation you need, in a massive study on female smokers in the United Kingdom, published in 2012. The research, published in The Lancet, reveals that women can gain more than a decade of extra life, if they quit smoking in their 30s or 40s.
While ditching tobacco has been proven to improve the health of both men and women, warding off conditions like heart disease and diabetes, this is the first long-term, large-scale analysis that quantifies the true cost of smoking, to the lifespan of women who do it.
Smoking patterns and mortality: More than a billion people smoke worldwide, and an estimated 20% of those are women, according to a 2011 review, also published in The Lancet. Each year, more than 5 million deaths are caused by tobacco smoking. Despite the fact more people are ditching the habit in North America, and moves by tobacco companies to reduce the amount of tar in cigarettes, smoking remains the leading preventable cause of death.
Because of historical differences in the smoking habits of men and women, however, the full risks to female smokers have not been seen until recently, argues a team of cancer epidemiologists led by Kirstin Pirie from the University of Oxford, in the UK. Many men born in the early 1900s started smoking at a young age, revealing the full risks of tobacco some time ago. Women, on the other hand, only began smoking heavily much later, with tobacco use peaking in the 1960s. Because many smoking-related illness set in years after the habit has begun, Pirie’s team writes, previous studies have likely underestimated the full mortality cost of smoking in women; only now can the risks be measured.
The Million Women Study: Between the years of 1996 and 2001, more than a million women in the UK were recruited into a study examining lifestyle habits, smoking frequency, cancer incidence, and mortality. After excluding women with existing or previous disease (like respiratory problems, cancer or stroke), a total of almost 1.2 million women remained to be tracked over a 12-year period.
All of the participants were contacted three years and again eight years after recruitment, with mortality rates computed at the 12-year mark. Thanks to each participant having a unique identifying number under the UK’s National Health Service, the research team had “virtually complete” information about cause of death.
What the researchers found: The results paint a dramatic picture of the risks of long-term smoking, and the benefits of quitting. Women who smoked throughout their lives had a mortality rate three times higher during the study period, than that of similar women who’d never smoked. Most of the deaths, or what the researchers call “excess mortality”, were caused by diseases associated with tobacco, including lung cancer, chronic respiratory problems, heart disease, and stroke. These results held, even after accounting for risk factors like obesity, fitness levels, alcohol consumption, and socioeconomic status.
Earlier quitting, better longevity: Women who quit at a younger age were able to avoid much of the serious illness associated with smoking. For example, the study results showed women who stopped before the age of 40, dodged more than 90% of the excess mortality caused by tobacco. Women who quit before the age of 30, did even better, avoiding the vast majority –- more than 97% -- of this excess mortality. Seen another way, quitting before the age of 40 leaves a woman with only 10% of the excess mortality faced by those who continue to smoke.
Stopping smoking early enough (before the age of 30 or 40), was shown to buy women about an extra 11 years of life.
Light smoking, heavy risk: Being a so-called “light” smoker still carried a serious increased risk of death over time, as Pirie’s team revealed that women smoking fewer than ten cigarettes per day still had twice the 12-year mortality rate of never-smokers.
Surprisingly, moves to produce cigarettes with less tar seem not to have had a great impact on mortality rates, according to the Million Women Study. The researchers point out that tar levels average less than 10 mg/cigarette throughout this study – and still appear to kill more than half of the women who smoke them – unless those women quit early enough. Pirie’s team cautions that “low-tar cigarettes are not low-risk cigarettes”.
Bottom line: Different methods like self-hypnosis, meditation, and even viewing photos manipulated to show how tobacco contributes to skin aging might help boost the motivation of women trying to quit smoking -- but there’s nothing quite like quantifying the number of years you might gain, by ditching this particularly dangerous habit. What would you do, with that extra decade of life?
- 10 Things to Stop Doing If You Want to Live Longer
- 10 Simple Ways to Motivate Yourself Towards a Healthier Lifestyle
- If you're ready to quit, why not read Quit Smoking 101, from About.com's Smoking Cessation Guide Terry Martin
Huxley RR, Woodward M. “Cigarette smoking as a risk factor for coronary heart disease in women compared with men: a systematic review and meta-analysis of prospective cohort studies.” The LancetOctober 2011; 378: 1297–305.
Kirstin Pirie, Richard Peto, Gillian K Reeves, Jane Green, Valerie Beral, “The 21st century hazards of smoking and benefits of stopping: a prospective study of one million women in the UK.” The Lancet. Published online October 27, 2012.
Smoking. US National Institutes of Health Medline Public Information Sheet. Accessed November 12, 2012.