COLUMBIA, Mo. -- Many young adults explore and define their sexual identity in college, but that process can be stressful and lead to risky behaviors. In a new study, students whose sexual self-definition didn't fall into exclusively heterosexual or homosexual categories tended to misuse alcohol more frequently than people who had a firmly defined sexual orientation for a particular gender, according to University of Missouri researchers. These findings could be used to improve support programs for sexual minorities.

"Bisexuals and students whose sexual orientation was in flux reported the heaviest drinking and most negative consequences from alcohol use, such as uncontrolled drinking and withdrawal symptoms," said Amelia Talley, MU assistant professor of psychological sciences in the College of Arts and Science. "Those groups reported drinking to relieve anxiety and depression at higher rates than strictly heterosexual or homosexual individuals. One possible explanation is that people who aren't either completely heterosexual or homosexual may feel stigmatized by both groups."

The study followed more than 2,000 incoming college students for four years. Each fall and spring, study participants were surveyed about their sexual self-identification, attraction and sexual behavior. The students fell into different sexual orientation groups. One was exclusively heterosexual, but there were several sexual minority groups: exclusively homosexual, mostly homosexual, bisexual and mostly heterosexual. The survey also asked about frequency of alcohol use, reasons for drinking, and negative consequences experienced as a result of alcohol use.

"Exclusively homosexual and heterosexual persons drank at roughly the same rate and reported drinking to enhance enjoyment of social situations," Talley said. "The other sexual minority groups tended to report more alcohol misuse. This suggests that it may be the stressful process of developing one's sexual identity that contributes to problematic drinking, just as people in any difficult situation in life may turn to alcohol to alleviate stress."

The study also found gender differences in sexual behaviors and self-definition of sexual identity.

"Females showed the greatest degree of sexual orientation fluidity," Talley said. "They were able to admit a certain degree of attraction to the same gender without defining themselves as completely homosexual." Talley suggested that "women may be more open to admitting to same-sex attractions because women are more likely to be objectified as sexual objects in our culture; hence, women are accustomed to assessing the attractiveness of other women in comparison to themselves."

Males tended to define themselves as either heterosexual or homosexual. Talley speculated that this may be because many males aren't aware that being "mostly straight" is a feasible alternative. Even a small degree of sexual attraction to other males may cause a young man to feel anxiety about his sexual identity due to strict masculine gender norms.

"Organizations could put our findings to use by providing a support network to help young people avoid using alcohol to cope with stress as they define their sexual identity," Talley said.

The study was published in the Journal of Studies on Alcohol and Drugs.

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