This study expands our knowledge of temporal patterns in purging and binge eating experienced throughout adolescence, finding that sexual orientation-related disparities emerge early in adolescence in both females and males and largely persist. Our study also underscores the importance of examining differences in health experiences patterned by gender and sexual orientation subgroup.
Our findings are consistent with those of Wichstrøm, who found in a representative sample of Norwegian high school students that youth with same-sex sexual experience were more likely to report bulimic symptoms than were peers without same-sex sexual experience.[11
] Wichstrøm also found elevated rates in the subgroup of youth who described themselves as having “incidental” same-sex attractions, who made up 12.8% of females and 4.5% of males in the 12-to-19-year-old Norwegian sample. This group is likely to be comparable to the subgroup of GUTS participants who describe themselves as “mostly heterosexual,” who make up approximately 8.3% of females and 4.1% of males in the GUTS sample in a similar age range. It is not known why “mostly heterosexuals” are more likely than heterosexuals to report purging and binge eating, but previous research in our cohort and other studies indicates that this group is at elevated risk for depressive symptoms[26
] and violence victimization,[16
] all factors that have been found to increase risk for eating disorder symptoms in adolescents.[28
] Prior research has identified bisexual populations as perhaps at uniquely elevated risk for mental health and substance use problems,[14
] an observation that our study partially supports. Among females in the GUTS cohort, bisexuals were at greater risk for purging for weight control but not binge eating compared to “mostly heterosexuals” and lesbians. In our sample, compared to heterosexual females, lesbians reported a higher prevalence of binge eating (though P=0.06), as did “mostly heterosexual” and bisexual females. Binge eating may contribute to higher rates of overweight particularly observed in lesbians compared to heterosexual women,[29
] but more research is needed to explore this relationship.
Findings from studies with adult samples suggest that the disparities we observed throughout adolescence are likely to persist to some extent in adulthood, especially in men. Studies of community-based and clinical samples have found gay and bisexual men to have greater likelihood of reporting weight concerns, body dissatisfaction, and dietary restraint than heterosexual men.[5
] Research findings among women have been less consistent, and several adult studies comparing lesbian and heterosexual women have found few differences between the groups.[5
] Feldman and Meyer found gay and bisexual men ages 18 to 59 years to report higher rates of bulimia than did heterosexual men, but they did not find significant differences comparing lesbian and bisexual women to heterosexual women.[7
] An explanation for the gender difference in consistency of findings may be due to the relatively high prevalence of eating disorder symptoms in heterosexual females (unlike their heterosexual male counterparts) and therefore the low magnitude of relative measures (e.g. odds ratios, risk ratios) of orientation disparities among women compared to the magnitude of disparities observed among males. Most studies to date may not have had sufficient sample sizes to detect statistically significant orientation group differences of low magnitude expected among women.
Our study extends the prior research in at least two important ways. First, we were able to examine patterns in prevalence across developmental periods throughout adolescence, revealing that disparities in purging and binge eating emerge as early as ages 12 to 14 years and largely persist through late adolescence. Interestingly, visual displays of our data presented in are suggestive of a possible downturn in prevalence in the lesbian and bisexual female groups and also in the gay (but not bisexual) male group by the older age periods, with rates of purging and binge eating moving toward those of heterosexual peers perhaps by young adulthood. Rosario et al. and others have proposed that integration of a lesbian, gay, or bisexual identity over time through adolescence may have positive effects on self-esteem and psychological health,[32
] though further research is needed to more fully explore hypothesized reductions in symptoms in lesbian and gay and perhaps other subgroups as they transition into adulthood.
Second, our study is substantially larger than most prior research and includes six waves of repeated measures, allowing us to document evidence that gender and orientation subgroup modify the relationship between sexual orientation and purging and binge eating in adolescents. The relative odds estimated within the male subsample for “mostly heterosexual,” bisexual, and gay males were substantially larger than those estimated within the female sample. That said, it is important to recognize that in most cases females within each orientation subgroup reported higher prevalence of purging and binge eating than did their male counterparts throughout the observed age period.
The emergence of disparities early in adolescence in both females and males suggests this vulnerability may be driven in part by factors shared in common by both genders, such as the types of factors posited in Minority Stress Theory.[12
] Earlier age of recognition and disclosure of lesbian, gay, or bisexual sexual orientation is linked with abuse and bullying victimization and psychological distress,[34
] and disapproval from parents is positively associated with stress[36
] and victimization by parents.[37
] In this context, it is plausible that lesbian, gay, bisexual, and “mostly heterosexual” youth in early and middle adolescence may adopt a range of unhealthful coping methods,[13
] including unhealthful eating and weight control patterns. Stress and negative affect have been found to be associated with symptoms of eating disorders.[38
Our study has several potential limitations. Generalizability of the findings is reduced by the cohort’s composition: More than 90% of participants are of white race/ethnicity and all are children of nurses. Nevertheless, GUTS recruitment was not based on sexual orientation, which therefore reduces sexual-orientation-related selection bias that can be common to samples recruited through lesbian, gay, and bisexual community settings. Small subgroup sizes for bisexual males and lesbians may have reduced stability of estimates for these groups. In addition, we did not examine other deleterious weight-control behaviors characteristic of clinical and subclinical eating disorders, such as excessive exercise, use of diuretics, and fasting nor did we conduct clinical interviews to establish diagnosis of an eating disorder.[3
] Disparities may also exist in these other behaviors and in full-criteria disorder and therefore warrant further study.
Health care providers working with youth need to be alert to the elevated risk of eating disordered behaviors in “mostly heterosexual,” bisexual, and lesbian/gay adolescents of both genders. Behaviors such as binge eating and vomiting, laxative or diuretic use, excessive exercising, and fasting for weight control have been linked with many harmful psychological and physiological effects on health,[1
] and these effects are particularly concerning when they coincide with developmental periods in which healthy growth and maturation are expected to occur. Lesbian, gay, bisexual, and “mostly heterosexual” youth engaging in any of these behaviors need to be evaluated for symptom severity and referred for appropriate treatment by providers who are sensitive to the specific needs of these populations. In addition, new research initiatives will need to examine hypothesized causes of disparities in order to develop preventive interventions that will be effective for these youth.