It’s just one cigarette, how much harm could it do?
A lot, actually, according to a new study published in the British Medical Journal.
The study found that for men, smoking just one cigarette a day comes with half the risk of coronary heart disease (CHD) as a man who smokes 20 a day. And for women, just one cigarette a day gives you one-third of the risk of CHD — which can result in chest pain or a heart attack — compared to women who smoke 20 cigarettes a day.
When researchers accounted for other variables, they found men who manage to limit their intake to a single cigarette each day increase their chances of getting CHD by 74 percent, while women up their chances by 119 percent compared to non-smokers.
The one-a-day habit also makes you more likely to have a stroke, with men experiencing a 30 percent increase and women a 46 percent one compared to those who never smoke, the study also found.
That’s why people should be wary of simply reducing their cigarette intake or switching to “safer” alternatives like e-cigarettes in the hopes of avoiding a heart attack or stroke, University of Ottawa professor Kenneth Johnson wrote for the British Medical Journal.
“The take home message for smokers is that any exposure to cigarette smoke is too much,” wrote Johnson, who was not involved in the study. “The message for regulators dealing with newly marketed ‘reduced risk’ products is that any suggestion of seriously reduced CHD and stroke from using these products is premature.”
“New tobacco products, such as e-cigarettes and heat-not-burn cigarettes, may carry substantial risk for heart disease and stroke.”
To conduct the study, researchers examined studies from 1946 to May 2015 to determine how the number of cigarettes a person smoked each day affected their health. They found men who go through 20 cigarettes a day have twice the risk of getting heart disease while women with the same habit have a 2.8 times greater chance compared to those who never smoked.
But don’t get discouraged if you’re struggling to fully wean yourself off cigarettes. Paul Aveyard, professor at the University of Oxford, told the BBC that reducing the amount of tobacco you inhale can still put you on the path toward a more healthy life.
“Those who try to cut down with the aid of nicotine, whether from nicotine replacement treatment or an e-cigarette,” he said, “are more likely to stop eventually and thus really reduce their risks from smoking.”
And when it comes to lung cancer, it’s best to quit cigarettes sooner rather than later, Norman Edelman of the American Lung Association told TIME.
The Centers for Disease Control and Prevention wrote that about 16 million people in the U.S. have a disease that originated from smoking — and 6 million people die each year across the globe from tobacco.
In the U.S., 1,300 people die each day from diseases brought on by cigarette smoke, the CDC estimates. Around 7 percent of those under the age of 18 in the U.S. are expected to die from tobacco-induced diseases if the current rate of smoking stays stable.
The bevy of risks that come with smoking cigarettes should be incentive enough to quit, said Carl Horton, a cardiologist at Texas Health Harris Methodist Hospital Cleburne.
“If you are a heavy smoker — if cancer doesn’t get you, then a heart attack or a stoke or (chronic obstructive pulmonary disease) will,” he told the Cleburne Times-Review. “When you stop smoking your risk for heart attack immediately decreases and your chance for having cardio disease, malignancies or cancer in the future also significantly decreases.”