Smoking costs the NHS about £5bn a year, which is up to four times the current estimated, according to new research.
The calculation comes from the British Heart Foundation health promotion research group at Oxford University, which says the usual figure, of between £1.4bn and £1.7bn a year, is out of date. It is based, they say, on cost estimates from 1991, which assume an annual death toll of more than 105,000 up to 2002.
Its new study, published in the British Medical Journal publication Tobacco Control, updates the figures by examining a range of reliable data up to 2005-2006, at which point one in four adults in the UK was a smoker. It included published research into the costs of treating smoking-related ill-health, information from the World Health Organisation from 2002 and routine data on smoking deaths in the UK, which is collected monthly.
It calculates that about 110,000 people died in 2005 directly as a consequence of smoking, which is about one in five of all deaths. Smoking caused more than one in four men's deaths and about one in 10 among women.
The number of deaths is similar to that in 2002, which "suggests that the overall numbers of deaths attributable to smoking have not changed much in the past 10 years", the authors write. Their estimated cost to the NHS of more than £5bn in 2005-6 is equivalent to 5.5% of the NHS budget.
They add that the costs are those of treating people who smoked in the past and do not reflect any public health success in persuading people to quit. Even so, they are an underestimate because they do not take account of the cost of people made ill through second-hand smoke.