When Vanessa Schick asks certain subjects in her studies if they’re sexually attracted to both men and women, they often tell her yes. But ask them if they’re bisexual and the answer isn’t always the same. Bottom line, there are countless shades of identity on the spectrum between totally straight and totally gay — if either thing even exists, which is debatable. But many say they specifically don’t want to identify as bisexual because of stigma. You’ve probably heard the stereotypes about bi people: They’re hypersexual, they can’t stay monogamous, they transmit sexually transmitted infections between straight and gay populations.

That type of thinking, called internalized biphobia, means that even bisexuals often have negative stereotypes about themselves. So it wasn’t the biggest surprise when Schick, a faculty member at the School of Public Health at the University of Texas Health Science Center at Houston, and her colleagues polled 1,500 adults and found that negative attitudes toward bisexuals span every race, gender and sexual orientation. Women, white people and those who identified as gay showed less bias — but it was still there.

What’s more surprising, though, is how that attitude might be affecting the health of bisexual Americans. Rice University sociology professor Bridget Gorman and her team were some of the first to look at extant data from the Institute of Medicine on race, gender and sexuality as well as health and class, and to tease out how gay Americans and bisexual Americans differ — statistically speaking. Turns out, it’s a significant difference. Bisexuals are more likely to be smokers, less likely to go to the doctor and more likely to be poor. Nearly 20 percent say they’re in poor or fair health, while it’s about half that for people who identify as gay or lesbian. “In bisexual adults we saw a lot of evidence of health risk, of factors that are factors of poor health,” Gorman says.

Bisexuals suffer from a lack of social support — the structures of friends, family and community just aren’t statistically as strong as they are for heterosexual or gay and lesbian populations.

In the past, studies tended to group all LGBT people together and draw conclusions from that — which is how something like a bisexual health crisis goes undiagnosed. And while studies like those from Gorman can tell us what’s going on, they can’t tell us why. Yet Schick’s work may get us closer to answering that question. “We know there’s double discrimination,” she says, meaning discrimination about bi people from both the gay and straight communities, or even the ever-popular assertion that bisexuality doesn’t exist.

For now, some bisexual people seem to get caught in a vicious circle: the phenomenon of bi invisibility, where they get treated as heterosexuals while they’re dating someone not of their gender and homosexuals when they’re in a same-sex relationship. This, experts say, contributes to the erasure of bisexuality — and helps perpetuate the stereotypes about it. In Europe, only 27 percent of bisexual women and 14 percent of bi men say they’re “out” in their workplaces, but that number jumps to 50 percent for gay men and lesbians. Gorman’s hunch is that bisexuals suffer from a lack of social support — the structures of friends, family and community just aren’t statistically as strong as they are for heterosexual or gay and lesbian populations, and emotional support is key to health.

That’s not to say there isn’t any support for the bisexual community. But Jen Yockney, who convenes the U.K.’s longest-running bisexual support organization, BiPhoria, admits that resources can be thin on the ground. Most of the money, resources and visibility go to organizations for gay men; lesbian-focused groups get a healthy bite too. Those aimed at transgender, bisexual and other individuals have to jostle for the little that’s left. Around two-thirds of the people who visit BiPhoria are coming out, Yockney estimates; of those, about a third previously identified as straight and another third as gay, but the rest are just seeking a community. “Often people come to us having identified as gay or lesbian and now finding that when they come out as bi, their gay social circle is less accepting,” Yockney says.

To be sure, there’s a lot of research left to be done on sexual minorities, as well as on how health disparities in the bisexual community play out along lines of class and race. That kind of academic work is driven by money, and often the money to support inquiries into bisexuality just isn’t there — even though, as Schick says, bisexual females actually make up the largest percentage of the LGBT community. Moreover, while researchers can make educated guesses, it’s impossible to say for sure exactly why there are health disparities between bisexuals and the rest of the country.

What is clear is that the bisexual community continues to be marginalized. When Schick moved to Houston, the sizable LGBT center didn’t have much programming aimed at bisexuals. She spoke to them, and now they offer a peer support group for this population. “It’s one of their most popular programs,” she says. “I don’t think people realize how big an issue it is, but moreover, they don’t realize how big the bisexual population is.”