Being married to a smoker can considerably increase your risk of stroke, even if you’re a non-smoker, suggests a recent study carried out by a team at Harvard University and published in the newest issue of American Journal of Preventive Medicine.

It is almost unanimously known the fact that smokers are far more likely to suffer stroke than non-smokers. However, about the passive smokers not much has been written. Thus, it should be knows that second hand smoke kills more than 50,000 non-smokers each year.

"This adds to the growing evidence that secondhand smoke is bad for you, and I hope that it will help people who want to stop smoking to know that it will probably be good for their spouse's health, too," said Maria Glymour, leader of the study and assistant professor of society, human development and health at the Harvard School of Public Health in Boston.

Now that smoking in public places has been banned, passive smokers are most likely to be exposed to tobacco smoke at home if they live under the same roof with people who regularly smoke.

In the study, researchers looked at records of more than 16,000 people aged 50 or over, as well as their spouses, over a period of an estimated 9 years. The findings are definitely alarming. If someone had never smoked, living with a smoker increased its stroke risk by 42 percent. If he or she had smoked at some point, but quit, the increase in risk was even higher, at no less than 72 percent. Having as husband or wife a former smoker didn’t show a higher risk, said the Harvard researchers.

Among other problems, tobacco smoking causes lung cancer, emphysema and cardiovascular disease, other researchers concluded. The World Health Organization informed that smoking cigarettes killed 100 million people around the world in the previous century and cautioned that in the 21st century it could kill one billion people worldwide.