Women who have never taken a puff of a cigarette are more likely to suffer from obesity and die of its associated illnesses than their smoking counterparts, scientists have said.
Experts believe this section of society is more likely to pile on the pounds, potentially leading to serious health problems including diabetes, heart attacks and strokes.
Their research suggests declining numbers of female smokers over the past few decades may also have had a direct impact on rising weight problems as fewer people suppress their appetites with cigarettes.
The authors, led by Laurence Gruer from NHS Health Scotland, reviewed the cases of 3,613 women who never smoked.
The group, recruited in Scotland between 1972 and 1976 when aged 45-64, was monitored for 28 years.
The results showed those who never touched tobacco were more likely to be overweight or obese than their fellow smokers – 60 per cent against 40 per cent – with the extra weight acting as an “important contributor” to premature death.
The highest rate of obesity among non-smokers was found in low income groups, according to the study published in the British Medical Journal.
Almost 70 per cent of women in this category were overweight or obese.
“You can certainly assume that if you are obese, you are more likely to die of things like diabetes, heart attacks and strokes,” Dr Gruer said.
However, his study – which also considered mortality rates in different sectors of society - found non-smokers who lived a healthy lifestyle were no more likely to die early if they were from a lower occupational group.
“If you never smoke and you keep your weight within the reasonable limit then even if you earn below average income and live in a more disadvantaged area, you can still expect to live a long and healthy life,” Dr Gruer said.
“You are not doomed to die early just because you happen not to have a high income or good job or live in a leafy suburb.
“It goes against the idea that if you live in a poor neighbourhood or came from a working class background, then your health will be worse, regardless.”
Johan Mackenbach professor at the Erasmus Medical Centre in Rotterdam welcomed the study but added: “It is important not to forget that smoking is a much stronger risk factor for mortality than most other risk factors, including obesity.”