Professor Glyn Lewis, from the University of Wales and Dr Andy Sloggett, from the London School of Hygiene and Tropical Medicine, studied data on suicides occurring between 1983 and 1992.

They found that unemployment was associated with a doubling of the suicide rate. Lack of job security was also a risk factor.

Other measures of socio-economic status, such as social class and housing tenure, were not associated with an increase in suicides. This contrasts with a strong link between depression and anxiety and low socio-economic status.

Access to a car cuts suicide risk

Access to a car was associated with a decreased risk of suicide despite the fact that men are increasingly likely to use poisoning with exhaust fumes as a method of suicide.

Writing in the British Medical Journal, the authors say: "Employment may have a particularly important role in defining an individual's place in the community, and unemployment could lead to alienation from the rest of society.

"This study could not adjust for some potential confounders but provides strong support for the possibility that reduction in unemployment would also reduce rates of suicide."