Compared with those who had never smoked, the men and women who smoked between one and four cigarettes a day were almost three times as likely to die of coronary artery disease.

Among women, smoking one to four cigarettes daily increased the chance of dying from lung cancer almost five times.

Men who smoked this amount were almost three times as likely to be killed by lung cancer.

However, due to the relatively small number of men that this applied to in the study sample, this finding could have been due to chance.

So-called "light" smokers were also found to have a significantly higher risk of dying from any cause - 1.5 times higher generally - than those who had never smoked, when researchers looked at deaths among those studied over the duration of the research.

Death rates from all causes rose as the number of cigarettes smoked every day increased.