Homeless people can expect to die 30 years before the average person, research has found.
A study showed that homeless men are dying at an average of 47 years old and homeless women at 43 years old, in stark contrast to the average age of death for the general population at 77 years.
The research, carried out by Sheffield University on behalf of homelessness charity Crisis, found that drug and alcohol abuse counts for just over a third of all deaths among homeless people.
Suicide is also nine times more likely among people living rough than the general population.
Meanwhile it found that deaths as a result of traffic accidents are three times as likely, infections twice as likely and falls are more than three times as likely to result in death.
The study, named Homelessness: A silent killer, showed that as expected, the causes of death for homeless people differ from those of the wider population, where disease is the biggest killer.
The links between drug and alcohol abuse and homelessness are well established and drugs and alcohol are known to be both a cause and consequence of living on the streets, it said.
Previous research has found that four out of five people start using at least one new drug after becoming homeless.
Leslie Morphy, chief executive of Crisis, said: "It is shocking, but not surprising, that homeless people are dying much younger than the general population. Life on the streets is harsh and the stress of being homeless is clearly taking its toll.
"This report paints a bleak picture of the consequences homelessness has on people's health and wellbeing. Ultimately, it shows that homelessness is killing people."