Five million UK adults are acting as carers for sick or older relatives, according to the latest figures from the NHS Information Centre.
In addition, more than one in five carers are providing more than 50 hours each week, a figure that has doubled from 10 per cent to 22 per cent of carers in the last nine years.
Just over a third of carers described the quality of their own life as good or better, 47 per cent saying it was "alright", with 17 per cent believing it was bad or worse.
Reacting to the data, Carers UK said it provided more evidence that the UK is undergoing a "rapid demographic shift", with urgent government action required.
"Unless we act to change the way our country supports disabled and older people and those who care, we risk condemning families to ill-health, poverty and isolation," said the organisation's chief executive Imelda Redmond.
Find the nearest Barchester care home.