A study of 40,000 Canadians has found single fathers are at the greatest risk of dying prematurely, compared to single mothers and partnered parents.

Single parenting appears to pose the greatest risk to the health of fathers rather than mothers, new research suggests.

An 11-year study of more than 40,000 people in Canada found single fathers were nearly three times more likely to die prematurely compared to single mothers and partnered parents.

The findings, published in medical journal The Lancet Public Health, demonstrated a need for public health policies to help identify and support these men to make healthy lifestyle choices, said lead author Dr Maria Chiu, Institute for Clinical Evaluative Sciences and University of Toronto, Canada.

"While our study does not identify the exact cause of this, we did find that single fathers also tend to have unhealthier lifestyles, which could be an important area to address to improve health in this high-risk group," said Dr Chiu.

For the study, researchers tracked the health of 40,490 people who took part in the Canadian Community Health Survey, including 871 single fathers, 4590 single mothers, 16,341 partnered fathers, and 18688 partnered mothers (average age 41-46 years).

The participants completed questionnaires giving details of their lifestyle and socio-economic status, including their fruit and vegetable intake, physical activity, and binge drinking.

This was then linked to their health records to identify medical conditions, how often they used health services, whether they died, and cause of death.

After a median of 11 years follow-up, 693 people had died.

Four per cent (35) of the single fathers had died, compared to two per cent (345) of the partnered fathers.

Partnered mothers were least likely to die over the follow-up period, with just 1.2 per cent dying.

The research also found single fathers ate fewer fruit and vegetables and were more likely to binge drink.

While more research is needed to understand the causes of death behind the increased mortality in single fathers, doctors should invest more time into this vulnerable group of men, said Dr Chiu.

"Doctors' appointments could be an opportunity for doctors to engage with single fathers to help them to improve their health. Research has shown that these conversations can help to motivate patients to adhere to treatment plans, make better decisions about their health, and influence their behaviour and recovery," said Dr Chiu.