The federal government spent millions of dollars in recent years researching why lesbians have a higher obesity rate than heterosexual women and gay men, according to funding records.

The ongoing National Institutes of Health study, now in its fourth year and scheduled to last another two, has cost about $3 million to date, the Washington Free Beacon reported in a recent article.

A summary of the research project said that nearly three-quarters of lesbians are overweight or obese. The rate is 25 percent higher than heterosexual females and almost “double the obesity risk of gay men,” the summary said.

The researchers, led by an epidemiologist at Brigham and Women’s Hospital in Boston, have already concluded that lower athletic self-esteem among lesbians may lead to higher rates of obesity and that lesbians are more likely to see themselves at a healthy weight when they are not, according to the Free Beacon report.

Researchers have also determined that gay and bisexual males had a “greater desire for toned muscles” than straight men. This apparently helps explain why gay men are generally more fit than lesbians.

By now, you’re probably wondering why the government is funding a study that, so far, has largely reinforced stereotypes of gays and lesbians. The project summary says that “racial and socioeconomic disparities are receiving increasing attention” and lesbian obesity is “of high public-health significance.”

The study of lesbian obesity has grabbed the attention of budget watchers, but it’s an easier sell than many of the federal government’s other science projects, since it directly involves a public health concern.

Every now and then, budget hawks highlight federally funded research projects that seem to have no clear benefit except to satisfy scientific curiosity.

Sen. Tom Coburn (R-Okla.) last year questioned the usefulness of a government-subsidized study of duck genitals in his annual “Wastebook.” Funding for the $385,000 research project came from the 2009 economic-stimulus bill.

One key finding from the duck study, titled “Conflict, Social Behavior and Evolution,” was that duck vaginas run clockwise in a corkscrew, while the penises run counterclockwise in a spiral pattern. That difference of anatomy prevents ducks from successfully mating until the females are ready, in which case their vaginas dilate and expand to negate the difference.

“The females are enormously, amazingly successful at preventing fertilization by forced copulation,” said Richard Prum, one of the Yale University researchers, who explained the study for a Politifact article.

Another researcher for the project, Patricia Brennan, argued in a Slate editorial that critics had misunderstood the purpose of the study, saying it was not intended to solve an immediate practical problem. “Basic science is an integral part of scientific progress, but individual projects may sound meaningless when taken out of context,” she said.

Brennan said federal funding is critical to advancing basic science, but she acknowledged that the question of whether the government should fund such research in times of economic crisis “deserves well-informed discourse comparing all governmental expenses.”