colleagues (2007) used population-based data from the National Survey of Family Growth to compare lesbians’ rates of obesity and being overweight with those of bisexual and heterosexual women. They found that lesbians were more likely to be obese or overweight than bisexual women, heterosexual women, and women who identified as “something else.” These data, in conjunction with findings of earlier studies, suggest that lesbians may be at greater risk for obesity and the health problems it may cause.
A number of studies have examined why lesbians, and in some cases bisexual women, are more obese and overweight than heterosexual women. Suggested theories include an association with the impact of minority stress, more positive body images, different exercise patterns, and childhood sexual abuse; however, insufficient research has been conducted to understand these associations.
Despite substantial changes over three decades, the HIV epidemic still exacts a severe toll on men who have sex with men in the United States (CDC, 2009a). However, rates of HIV diagnosis among all age groups are higher in black men who have sex with men than in other racial or ethnic groups of men who have sex with men in the United States (Hall et al., 2007). Given the magnitude and distribution of unrecognized HIV infection among young men who have sex with men, especially black men who have sex with men, the HIV epidemic continues at a rapid pace in this population, at least in part because many young HIV-infected men who have sex with men are unaware of their infection and unknowingly expose their partners to HIV (MacKellar et al., 2005). Studies also have found HIV prevalence to be substantially greater among male-to-female than among female-to-male transgender persons (Clements-Nolle et al., 2001) and the prevalence of HIV/STIs to be low among white and very high among Latino and black male-to-female transgender persons (Nuttbrock et al., 2009b).
Numerous risk factors for HIV transmission among gay and bisexual men have been identified, including lack of knowledge of HIV serostatus (Marks et al., 2009), nonsupportive peer norms (Hart et al., 2004), optimistic beliefs about HIV treatment (Ostrow et al., 2002; Sullivan et al., 2007), greater numbers of male sexual partners, unprotected intercourse with HIV-positive partners, and amphetamine or heavy alcohol or drug use before sex (Koblin et al., 2006). While use of the Internet to obtain partners has been increasing among men who have sex with men, the evidence appears to be inconclusive as to whether Internet use encourages or discourages risky sexual behavior (Carballo-Dieguez et al., 2006; Garofalo et al., 2007).
Notably, there is conflicting evidence on risk behavior in men who have sex with both men and women, regardless of whether they identify as