TV presenter Amanda Lamb swapped A Place in the Sun for a place at the tea table, to highlight the need for more volunteers to combat isolation among older people.
The charity arranges free monthly Sunday afternoon tea parties for people aged 75 and over who are living alone, to relieve loneliness and help them make new friends.
It needs more volunteers to host the gatherings and drive elderly guests to and from the venue each month.
The charity, which is celebrating its 50th anniversary this year, was last month chosen by new Hounslow mayor Nisar Malik as one of the two good causes he will support during his year in the chains.
There is a waiting list for people wishing to attend the tea parties in Hounslow, where more volunteers are needed so new groups can be launched.
Speaking about the tea party, which took place on May 17, Amanda Lamb said: "I was very close to my grandmother, and it was heart-breaking to know how lonely she was following the sudden death of my grandfather, to whom she had been married for almost 55 years.
"I think she would have really enjoyed an afternoon like this. Having spoken to the guests here today its evident how much they look forward to the tea parties and how overjoyed they are to be here."
Anyone interested in volunteering can call Jane Vasudevan, the charity's south London development officer, on 020 7240 0630, or email firstname.lastname@example.org.