Cutting back on smoking is a noble goal, but simply decreasing the amount of cigarettes you smoke—rather than quitting entirely—isn't as helpful as you might think when it comes to the health risks of tobacco use. ABC News reports that new research published in the BMJ finds that smoking just one cigarette a day still increases the risks of heart disease and stroke significantly.

Led by researchers from University College London and King’s College London, the study found that compared to not smoking at all, smoking one cigarette a day resulted in a 46 percent greater risk of heart disease and a 25 percent greater risk of stroke for men, and for women, a 57 percent greater risk of heart disease and 31 percent greater risk of stroke. Even if a person cuts down from smoking 20 cigarettes a day to one, the study found, the risks of developing heart disease and stroke are only halved—not reduced by 95 percent, as would be proportional. (Previous research has found that lung cancer risk, by contrast, decreases proportionally depending on the number of cigarettes smoked per day.)

The researchers examined 141 previous studies, reported in 55 publications, analyzing the risks of heart disease and stroke among men and women who smoked. The studies each examined risks of light smoking (defined as one to five cigarettes a day) and the risks associated with heavy smoking, or 20 cigarettes per day. The researchers adjusted for whether the studies considered factors like age, cholesterol, and blood pressure, all of which can also impact a person’s risk of heart disease and stroke.

The findings show that any amount of smoking carries high risks. While one cigarette a day might seem like nothing to a heavy smoker, its impacts on the body are significant, and shouldn't be underestimated, either by smokers or by their doctors.

[h/t ABC News]