Research shows that a disproportionate amount of homeless youth in the United States identify as lesbian, gay, bisexual or transgender, or LGBT. Researchers suggest that this is primarily a result of hostility or abuse from the young people's families leading to eviction or running away. In addition, LGBT youth are often at greater risk for certain dangers while homeless, including being the victims of crime, risky sexual behavior, substance abuse and mental health concerns.
Although specific estimates of the percentage of United States homeless youth who identify as LGBT vary widely, estimates generally fall somewhere between 11 and 40 percent. Barriers to a more definitive percentage include the lack of a nationally representative study and the possibility of underreporting due to stigma associated with identifying as LGBT. The city from which the sample is drawn for each study may also account for a difference in estimates. For example, one 2004 study at the University of Nebraska Lincoln noted that while estimates based on samples from Los Angeles range from 25 to 40 percent, a 1999 study of small and medium Midwestern cities concluded that only 6% of homeless youth there identified as LGBT. According to the authors of this study, geographical location could affect these numbers. For example, a due to the higher risk of coming out in rural, midwestern cities, youth may be more likely to either stay closeted there or to migrate to larger cities. Further, the authors continue, the differences might reflect differences in the ages of the samples in the different studies, or other differences in sampling methodology. The study concludes that when taken together, a general consensus can be found among the studies that 20% of homeless youth in magnet studies identify as gay, lesbian or bisexual, with the number being slightly lower in nonmagnet cities. Finally, in a 2012 study, legal expert Nusrat Ventimiglia noted that studies focusing on the number of transgender youth who experience homelessness are less prevalent, and therefore including youth who identify as transgender but not as gay, lesbian or bisexual could result in an estimate of 40 percent.
Researchers have posed a few core explanations for the overrepresentation of LGBT youth in the general United States homeless youth population. LGBT youth are more likely to be homeless because they run away or are evicted due to family conflict surrounding their sexual orientation or behavior. This explanation is supported by a 2011 survey study of a representative Massachusetts high school sample that found that LGBT youth were no more likely to be homeless and living with their parents than non-LGBT youth. Therefore, according to the study's authors, it may not be that LGBT youth are more likely to be part of a homeless family, but rather that their higher rate of homelessness is caused by being more likely to be evicted or run away. A 2008 study using in-person interviews found that among youth who experienced homelessness for more than six months, lesbian, gay, and bisexual youth were more likely than heterosexual youth to report being verbally or physically harassed by family. In addition, LGBT youth are more likely to be homeless due to physical or sexual abuse experienced at home. The Hetrick-Martin Institute showed that among homeless queer girls aged 13–15 in New York City, that 50% of them were homeless because they were fleeing familial corrective rape. In the background of both these explanations is the fact that, since the family conflicts associated with LGBT youth occur relatively late in a youth's development, LGBT youth are much less likely to be placed in foster care. Those who are placed in a foster home find an unwelcoming or hostile environment, and a study on the New York City Child Welfare System reported 78% of LGBTQ youth were kicked out, or ran away from their foster home as a result. Finally, a number of other factors that lead to increased risk of homelessness in adolescents disproportionately affect LGBT youth, such as experiencing conflict at school.