Just one cigarette a day can increase a person’s risk of heart disease and stroke, a study has found, dispelling the myth that cutting back, not quitting altogether, can eliminate health issues. The study found that just one cigarette a day can increase a person’s chances of heart disease by about 50% and chances of a stroke by 30% than people who have never smoked. The bottom line is that there is no safe level of smoking when it comes to heart disease and stroke. Cardiovascular disease, not cancer, remains the greatest mortality risk for smokers, accounting for approximately 48% of smoking-related premature deaths. And while the number of people who smoke in the UK has been falling, the percentage of people smoking one to five cigarettes a day has been steadily rising, researchers said. However, cutting down on cigarettes is always a good start and people who do so are more likely to quit in the long-run. Prof Allan Hackshaw from the UCL Cancer Institute at University College London, who led the study, said: "There's been a trend in quite a few countries for heavy smokers to cut down, thinking that's perfectly fine, which is the case for things like cancer. "But for these two common disorders, which they're probably more likely to get than cancer, it's not the case. They've got to stop completely." For the study, the researchers at UCL analysed data from 141 separate smoking-related studies and published their findings in the BMJ.