More women than men over the age of 45 are smoking, according to a report by the Office of Tobacco Control, which shows that older women, in particular, find it harder to quit than men.
The study shows that women are more likely to try to give up smoking but are less successful than men.
The report, Irish Women and Tobacco, shows females start smoking at a later age than males but keep on smoking later.
Dr Harry Comber, director of the National Cancer Registry, said the findings "suggest strongly that women need intensive, organised and prolonged support if they are to quit smoking and that the nature of this support may be different from that needed by men".
Predicting that by 2020 lung cancer will be a predominantly female disease, from being a mainly male disease for the past 50 years, he said that "smokers need the same level of support in fighting their addiction as heroin addicts, because they have at least as high a rate of relapse and addiction-related mortality as heroin addicts".
Currently about 600 new cases of lung cancer are reported annually in women, compared to approximately 900 in men.
The rate of lung cancer for men is dropping and by 2020 the statistics are expected to be equal at about 800 new cases and 750 deaths a year.
Dr Comber said that about 99 per cent of lung cancer cases are tobacco-related.
The treatment is quite radical, the survival rate is very poor and the best approach is to put resources into prevention.
Women are motivated to give up for personal health concerns, price increases, the birth of a child, pregnancy or the death of a family member from a smoking- related illness, according to the chairman of the OTC, Dr Michael Boland. He said it was "important to address the question of why women are more likely to continue smoking than men".
The research, conducted by TNS mrbi for the OTC, shows that overall some 30 per cent of the population smokes, 31 per cent of men and 29 per cent of women.
Some 49 per cent of males aged 18 to 44 smoke, compared to 38 per cent of females in that age group.In the over-45s, however, 27 per cent of women smoke, compared to 21 per cent of men.
Some 25 per cent of females started smoking over the age of 17 compared to 12 per cent of males. Men smoke an average of 18 cigarettes a day compared to 14 for women, and "in general, the present generation of young women are no more or less likely to smoke than young men," according to the report's authors.
Some 68 per cent of women tried to give up smoking compared to 61 per cent of men, but the study shows that men are likely to make more attempts to quit.
Ms Joan Carmichael, assistant general secretary of ICTU, said that women "seem more aware of the health consequences of smoking for men and for their children, but not for themselves. We need to change that attitude."
A nationally representative sample of 1,503 people, including a "booster" sample of interviews with 8 to 17-year-olds, was surveyed in August 2002 for the report.
Mr Damien Loscher, deputy managing director of TNS mrbi, pointed out that more than 90 per cent of women support smoking bans in public areas, but support dropped to 86 per cent for a ban in hairdressing salons and barbers.
A question on banning smoking in pubs and restaurants was not asked but conducted in separate TNS mrbi research for the OTC and published in June.
It showed 68 per cent of men supported the ban and 66 per cent of women.
