People who live on the streets die an average of 30 years before the general population, with drugs and alcohol the biggest killers

Homeless people can expect their lives to be about 30 years shorter than the average in the United Kingdom, with a likelihood of dying at around 47, an age of death comparable to that found in the Congo, according to a report by the charity Crisis.

Homelessness: A Silent Killer reports that homeless people in the UK who suffer the stresses and strains of alcoholism and substance abuse live only a little longer than those in the poorest countries, with the average age of death at 47 for men and 43 for women. This compares with 77 for the general population. The research, by Sheffield University, calculated that drug and alcohol abuse were responsible for just over a third of deaths among the homeless. They were also nine times more likely to kill themselves than the general public, and twice as likely to die of infections.

Leslie Morphy, chief executive of Crisis, said: "It is shocking … 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." Crisis warned that current NHS services do not meet the needs of homeless people and are at risk under the government's reorganisation of the NHS.

The charity was concerned that even while the health service was seeing rising budgets, the homeless were not considered a priority and that in a time of flat funding it was "clear that more needs to be done to tackle the health inequalities that persist for homeless people".

Morphy added: "Homeless people are amongst the most vulnerable in our society and it is clear that despite significant investment in the NHS they are not getting the help they need to address their health issues. Government must do more to improve the health of single homeless people and ensure they can access mainstream and specialist services.

Alex Bax, chief executive of London Pathway, a specialist homeless charity that works closely with University College Hospital, said services would only improve if the health outcomes of homeless people were made an explicit priority for all of the NHS. A separate report reveals almost 70,000 children will wake up on Christmas Day in temporary accommodation, without a permanent home to call their own.

According to government figures highlighted by Shelter, the housing and homelessness charity, there are currently 69,846 children in England living in temporary accommodation such as hostels, bed and breakfasts and refuges. With waiting lists lengthening and the government's cuts to housing benefit, there are worries that swelling numbers living in temporary shelter will become a permanent feature.

Kay Boycott, Shelter's policy director, said: "It's simply not right that in an affluent nation like ours, thousands of children will wake up on Christmas day wanting nothing more than a permanent roof over their head. We cannot underestimate the damage homelessness has on children's lives. They often miss out on vital schooling, because they are shunted from place to place and many become ill by the poor conditions they are forced to live in."

• This article was amended on 22 December 2011 because a heading and a text reference described 47 years as the "life expectancy" of homeless people in the United Kingdom. In fact, this was the average age for people (more specifically, men) who were homeless when they died - a different matter from life expectancy.