Almost one in three people aged 80 and older are providing vital, unpaid care for their loved ones, despite many suffering severe health issues of their own, according to research. The figure has increased by nearly a quarter in eight years.

This invisible army of oldest and most vulnerable people in the UK provide a total of 23m hours of unpaid care a week, or 1.2bn hours of care a year, according to figures from Age UK.

“Nearly a million over 80-year-olds are gifting the government a whopping £23bn a year and it’s high time these fantastic older people got something back in return,” said Caroline Abrahams, charity director at Age UK.

“Almost all of them willingly provide care for the person they love, typically a sick or disabled husband or wife, son or daughter, but by repeatedly failing to sort out our social care system the state is exploiting their goodwill and often leaving them to manage incredibly difficult situations alone,” she added.

The Age UK analysis shows that seven out of 10 carers aged 80 and over have long-standing health problems of their own, with nearly half having difficulty with moving about at home, walking, or lifting, carrying or moving objects.

“The burden placed on these older carers’ shoulders is not only physical and emotional, but financial too because after years of government underfunding so many older people who need care are having to pay for it themselves, wiping out the savings they’ve worked hard for all their lives, and sometimes resulting in the family home having to be sold,” Abrahams added.

“The staggering amount of hours of caring a week comes at a cost to carers’ own health and wellbeing, many of whom already have their own long-term health conditions, and are unable to leave the home or get sufficient breaks from their caring duties,” said Abrahams.

Len, aged 84, is a full-time carer for his wife. “I have only one hand, arthritis of the spine, nodules on the nerve canals in my spine and I’ve suffered from two strokes. I don’t have time to think about me! I didn’t even realise I had had one stroke, let alone two,” he said.

“We’ve each worked for most of our lives, paying our taxes, which we still pay on our pensions, which seems grossly unfair,” he added.

Almost a quarter of carers in this age group are caring for more than 35 hours a week, while a further 13% are caring for more than 20 hours a week. As our population continues to age, it is estimated that there will be 4.6 million people aged 80 and over by 2030.

Meanwhile, the total number of carers aged 65 and over who are providing informal care for another person has risen from 2.7 million to 3.3 million in the last 8 years.

Sally Copley, director of policy and campaigns at Alzheimer’s Society, said: “Dementia is heartbreaking for families and it is utterly unacceptable that a spiralling number of people over 80 are facing a dreadful double whammy when it comes to dementia care. Not only are they dealing with partners and loved ones developing dementia, they are also shouldering the gruelling pressure of caring for them alone – because professional care comes with a huge price tag, can be extremely hard to access and too often still does not meet the specific needs of people with dementia.

“The way their goodwill is being exploited by our government is unfair and unacceptable,” she added. “Boris Johnson promised that he would ‘fix the crisis in social care once and for all’, and there will be justified outrage from 850,000 people with dementia and their families if he doesn’t.”

A Department of Health and Social Care spokesperson said: “We recognise the selfless contribution that carers make for their loved ones. We are determined to find a long-term solution to the challenges in social care to make sure every person is treated with dignity and offered the security they deserve and will outline next steps shortly.”