The US National Institute for Health (NIH) has collaborated with researchers from the University of Pittsburgh' Magee-Women's Research Institute to study the sexual habits of obese girls.
The NIH has allocated $466,642 to find out how often they have sex and why they are less likely to use protection when they do.
"Obese girls consistently report having fewer dating and sexual experiences but more sexual risk behaviours (like condom non-use) once they are sexually active," the statement stated.
The study would compare sexual relationships between obese girls and non-obese girls, the Daily Caller reported.
A similar study last year examined how being lesbian or gay affects one's weight and health.
"The findings suggest that lesbian women are more likely to be over-weight or obese compared with their heterosexual peers, though less is known about gay men and bisexuals," an extract from the study stated.