Introduction Sexual minority college students (i.e., those not identifying as heterosexual, or those reporting same-sex sexual activity) may be at increased risk of poor mental health, given factors such as minority stress, stigma, and discrimination. Such disparities could have important implications for students’ academic achievement, future health, and social functioning. This study compares reports of mental disorder diagnoses, stressful life events, and frequent mental distress across five gender-stratified sexual orientation categories.

Methods Data were from the 2007–2011 College Student Health Survey, which surveyed a random sample of college students (N=34,324) at 40 Minnesota institutions. Data analysis was conducted in 2013–2014. The prevalence of mental disorder diagnoses, frequent mental distress, and stressful life events were calculated for heterosexual, discordant heterosexual, gay or lesbian, bisexual, and unsure students. Logistic regression models were fit to estimate the association between sexual orientation and mental health outcomes.

Results Lesbian, gay, and bisexual students were more likely to report any mental health disorder diagnosis than were heterosexual students (p<0.05). Lesbian, gay, bisexual, and unsure students were significantly more likely to report frequent mental distress compared to heterosexual students (OR range, 1.6–2.7). All sexual minority groups, with the exception of unsure men, had significantly greater odds of experiencing two or more stressful life events (OR range, 1.3–2.8).