The US National Institutes of Health (NIH) is to spend $1.5 million (£1.01 million) on a study to learn why 75% of lesbians are obese and why gay men are not.

Over the past few years, several pieces of research have shown lesbians are more likely to be obese compared to gay and bisexual men.

Brigham and Women’s Hospital in Boston, Massachusetts, has received two grants administered by NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) to study the relationship between sexual orientation and obesity.

Robert Bock, press officer for the NICHD said: “Obesity is a serious public health problem affecting a large proportion of the US. The study is examining reasons why the risk of obesity varies according to sexual orientation, in order to inform the development of future strategies to prevent obesity.”

“Our study has high potential for public health impact not only for sexual minorities but also for heterosexuals, as we seek to uncover how processes of gender socialisation may exacerbate obesity risk in both sexual minority females and heterosexual males,” researchers said.

The project is being led by S. Bryn Austin, Director of Fellowship Research Training in the Division of Adolescent and Young Adult Medicine at Boston Children’s Hospital.