Women who juggle a career, motherhood and a long-term relationship are more likely to be healthy over time, a new study suggests.

British researchers analyzed data tracking the health of more than 2,000 Britons born in 1946 until they reached age 54.

Women who played multiple social roles were less likely to report poor health or be obese in middle age compared with homemakers, single mothers or childless females, the team found.

At age 26 and 54, participants reported on their health, marital status, work history and parenthood.

A nurse also recorded heights and weights during face-to-face interviews at their homes.

Anne McMunn of University College London and her colleagues concluded good health among women is more likely to be the result, rather than the cause, of adopting several roles.

Obesity was most common (38 per cent) among long-term homemakers,and least common among women who worked in all three roles.

"Women who occupied multiple roles over the long term reported relatively good health at age 54 and this was not explained by early health," they wrote in the June issue of the Journal of Epidemiology and Community Health.