Homelessness is deadly. Living on the streets contributes to rapid health deterioration, increased hospitalization, and, in some cases, death. For vulnerable subgroups, such as street youth, people with mental illness, young women, and the elderly, the risk of mortality when compared to the housed population can be especially high. 

Homelessness makes it difficult to manage chronic illness and adhere to treatment regimens; regularly have healthy meals; and access hygiene care. Exposure to harsh elements and violence and comorbidity of health issues can have a negative impact on health, and homelessness has been shown to trigger relapses in substance use and abuse.