MELBOURNE: Lesbians and bisexual women are less healthy than their heterosexual counterparts, according to a new study. The study, by the WA Centre for Health Promotion Research, looked at identity, community connectedness, legal and illegal drug use, diet and nutrition, physical activity, cancer screening, mental health, harassment, safe sex practices and accessing health services.

It found smoking rates in lesbians and bisexual women were almost double that of the broader female community. Alcohol use was also higher, with about 30% in this group exceeding the national alcohol guidelines each week.

Lesbians and bisexual women drank more alcohol than heterosexual women and drank it more often, associate researcher Jude Comfort said. "We're talking about a group that socialises in a different way, around pubs and clubs," she said.

The findings confirmed other research showing lesbians and bisexual women had more health problems than heterosexual females.

"I would suggest one of the biggest issues is the marginalisation of lesbian women," Comfort said. Internalised and externalised homophobia could also affect health.

"Internalised homophobia is whether they are happy with their own sexuality, or if they give themselves a hard time over it," Comfort said. "There are issues of self-esteem."

The study also found about 30% of lesbians and bisexual women had been diagnosed with depression; 20% were having treatment for a mental health problem; 20% were overweight and 23% obese.

Comfort said that in general, health systems had been slow to respond because they were seldom built with sexual minorities in mind.

"It could be argued that sexual orientation is a social determinant of health... yet there are few targeted programmes which deal with general healthy lifestyle issues with this population. "Obviously there are lesbians who are healthy, but taking the results as a whole, the figures are alarming."