Female smokers lose at least 10 years of life on average, but quitting smoking before age 40—and preferably well before the age of 40—avoids more than 90% of the increased risk of dying caused by continuing to smoke, according to the largest-ever [removed]study[/removed] of smoking among women in the United Kingdom. The Oxford University-led study, published in The Lancet, shows that the hazards of smoking for women are greater than previous studies have suggested—but also that quitting has bigger benefits than previously thought.
Two-thirds of all deaths of smokers in their 50s, 60s, and 70s can be attributed to smoking, the results indicate, since most of the difference between smokers and non-smokers comes from smoking-related diseases, including lung cancer, chronic lung disease, heart disease, and stroke.
But women who stopped smoking around age 30 avoided 97% of their increased risk of premature death due to cigarettes.
[removed]Sir Richard Peto[/removed], professor at the University of Oxford, one of the study’s lead authors, says, “Both in the UK and in the USA, women born around 1940 were the first generation in which many smoked substantial numbers of cigarettes throughout adult life. Hence, only in the 21st century could we observe directly the full effects of prolonged smoking, and of prolonged cessation, on premature mortality among women.”
Peto notes that, male or female, “smokers who stop before reaching middle age will on average gain about an extra ten years of life.”
The Million Women Study recruited 1.3 million women aged between 50 and 65 in the years from 1996 to 2001. Participants completed a questionnaire about their lifestyle, medical and social factors, and then took another survey 3 years later. The researchers used National Health Service (NHS) records to track any deaths of participants, and the cause of death, over an average of 12 years from the time the women first joined the study.
At the start of the study, 20% of the study participants were smokers, 28% were ex-smokers, and 52% had never smoked. The researchers found that those women who were still smokers when surveyed 3 years later were nearly three times as likely as non-smokers to die over the next 9 years.
The researchers also showed that risks among smokers increased steeply with the amount smoked. And even for light smokers having between one and nine cigarettes a day, death rates were double those for non-smokers.
Source: Oxford University