A free 24-hour dedicated helpline for older people across the UK has been launched by Esther Rantzen.
'The Silver Line' aims to combat loneliness in the over-65s by providing friendship, information and advice through calls to trained volunteers.
The Department of Health has said that loneliness causes serious physical and mental damage. More than half of the UK's over-75s live alone.
Esther Rantzen, chair and founder of The Silver Line, said she hoped the phoneline number, 0800 4 70 80 90, would be remembered by all older people when they needed friendship or advice.
"We will signpost them to the services in their community, and by showing them we value them and care about them we will restore their confidence and feelings of self-worth."
She added: "It is tragic that older people are so undervalued and isolated that they believe life is not worth living and that they are no longer part of the human race."
Last year, the Campaign to End Loneliness estimated that more than a million people in the UK feel trapped in their homes and around five million older people consider television their main form of company.
Recently the Health Secretary Jeremy Hunt said it was shameful that as many as 800,000 people in England were "chronically lonely".
Volunteers answering helpline calls will be encouraged to befriend older people and make regular friendship calls to them over a period of months.
Care and Support Minister Norman Lamb said: "In our busy lives we too easily forget the thousands of older people who often go for days without seeing or speaking to anyone, or rely on the television for company.
"This service will help provide people with the companionship and support they deserve in their older years."
During an earlier pilot phase in the North East and North West of England, the Isle of Man and Jersey, the helpline was able to answer 7,000 calls from older people.