Smoking is 25 per cent more likely to give women heart disease than men, a new US study has found.
Toxic chemicals in tobacco smoke may have a more potent effect on women due to biological differences, scientists believe.
US researchers analysed pooled data on around four million individuals from 86 studies.
After adjusting for other risk factors, they found the increased risk of heart disease linked to smoking was 25 per cent higher for women.
The longer a woman smoked, the greater her heart disease risk was compared with that of a man who had smoked for the same length of time.
A woman's extra risk increased by 2 per cent for every additional year she had been smoking.
The findings are published today in the Lancet medical journal.
Authors Dr Rachel Huxley, from the University of Minnesota, and Dr Mark Woodward, from Johns Hopkins University, of Maryland, wrote: "Women might extract a greater quantity of carcinogens and other toxic agents from the same number of cigarettes than men.
"This occurrence could explain why women who smoke have double the risk of lung cancer compared with their male counterparts.
"Physicians and health professionals should be encouraged to increase their efforts at promotion of smoking cessation in all individuals.
"Present trends in female smoking, and this report, suggest that inclusion of a female perspective in tobacco-control policies is crucial."
In the UK, 21 per cent of women and 22 per cent of men smoke cigarettes.
PA