Smokers need to quit cigarettes rather than cut back on them to significantly lower their risk of heart disease and stroke, a large BMJ study suggests.
People who smoked even one cigarette a day were still about 50% more likely to develop heart disease and 30% more likely to have a stroke than people who had never smoked, researchers said.
Cardiovascular disease, not cancer, is the greatest mortality risk for smoking, causing about 48% of smoking-related premature deaths.
While the percentage of adults in the UK who smoked had been falling, the proportion of people who smoked one to five cigarettes a day had been rising steadily, researchers said.
Their analysis of 141 studies, published in the BMJ, indicates a 20-a-day habit would cause seven heart attacks or strokes in a group of 100 middle-aged people.
But if they drastically cut back to one a day it would still cause three heart attacks, the research suggests.
The researchers said men who smoked one cigarette a day had about a 48% higher risk of developing coronary heart disease and were 25% more likely to have a stroke than those who had never smoked.
For women, it was higher – 57% for heart disease and 31% for stroke.
Prof Allan Hackshaw at the UCL Cancer Institute at University College London, who led the study, told the BBC: “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.

more at BBC.com