The next time you’re tempted to light up, remember this: Every cigarette you smoke reduces your expected lifespan by 11 minutes, according to researchers at the University of Bristol in England. That means that 10 cigarettes a day for 10 years takes more than nine months off your life.

Tobacco was responsible for the deaths of 100 million people in the 20th century, and the World Health Organization estimates that in the 21st, cigarettes and other tobacco products could kill up to 1 billion. Use the information below to determine how cigarette smoking could affect your chances of living to a ripe old age.

We invited readers of Essence and All You magazines to send in their stories about quitting smoking—some successful, some not. Here are some of the responses that came in. View the slideshow.