The New York Times reports a new study published in JAMA which found that even for smokers who are not yet prepared to quit, taking medication over time can significantly improve their chances of eventually leaving the deadly habit behind. Previously set guidelines have told doctors only to prescribe medications such as Chantix once a specific quit date has been set. A third of the study participants who received the drug were able to quit smoking within six months, compared to only six percent of the control group. Killing more than 480,000 Americans each year, smoking is the largest preventable cause of death. While the smoking rate has declined significantly over the years, that rate has slowed in more recent years.