Young people are being "locked out" of Britain's democratic process because of a rapidly ageing population, a report has warned.
The Intergenerational Foundation, a think tank, said there would be many more voters in their 50s at the 2020 general election than in their 20s or 30s.
It warned that this meant even more government policies aimed at older people – in a bid to attract their vote – and fewer offers for young people.
The report, released on Thursday, said young voters had already suffered the "systematic removal of their welfare protections" – such as housing benefit, unemployment benefits and maintenance grants – to fund £5 billion of "universal benefits" for the old.
To counter Britain's changing age profile, older people must be encouraged to vote in the long-term interests of their children and grandchildren, it said.
At the 2015 general election, the "median actual voter age" was 51. That will rise to 52 at the next one in 2020, and to 55 in 2040. Those medians take into account voter registration and turnout rates.
The report also pointed out that an ageing electorate was more likely to move to the right. In 2015, nearly half (47%) of over-65s voted for the Conservative party compared to 27% of 18-24-year-olds.
The number of elderly people is set to increase rapidly in the coming years because the "baby boom" generation – the rush of babies born between 1946 and 1965 – are feeding through into old age. It means that "olderpeoplearemassivelyoutvoting theyoung", according to the report.
Angus Hanton, co-founder of the Intergenerational Foundation, said: “The changing age profile of voters is leading Britain towards a gerontocracy run by the old for the old.
"Where once the interests of the old and young were balanced out by births and deaths, we are now seeing a new demographic shape as people live for longer.
"This has serious implications for our democratic process if older voters choose to vote in their own interests and not in the long-term interests of their children and grandchildren, society and the environment. Unless urgent action is taken, younger generations will be increasingly locked out of the democratic process.”