Women over 55 are "invisible" on British TV, broadcaster and writer Dame Joan Bakewell has said.
Dame Joan, who has been made a champion of the elderly by the government, said it was "unhealthy" for broadcasters not to reflect the wider population.
She spoke after presenter Selina Scott won a settlement from Five after suing the channel for age discrimination.
Dame Joan, 75, said it was "a matter of legitimate equality" that older women be seen on TV.
Scott, 57, was reportedly being lined up to provide maternity cover for Five News host Natasha Kaplinsky, but was subsequently overlooked.
She took legal action against the broadcaster, which has now apologised for the offence it caused and settled out of court for a sum reported by newspapers to be £250,000.
It was announced last month that Dame Joan had agreed to be a Voice of Older People, acting as an "independent and informed advocate" on older people's issues.
Speaking on BBC Radio 4's Today programme on Saturday, she said Scott's case should encourage broadcasters to value older talent more highly.
"I think the fact that people are phased out, people like Moira Stuart and Selina - out of the public eye - when they become a certain age is a real disadvantage to serious broadcasting," she said.
"There's a whole segment of the British population that does not see its equivalent in serious broadcasting and that is women over 55.
"Now, that is not healthy for a broadcasting organisation's relationship with its audience. The public should be represented on the screen in various colours, forms, sexualities, whatever."
Dame Joan said quotas of older women on screen were not the answer, but the "attitude to recruitment and the development of talent" must change.
"There's no reason why the women should depart while the men stay in office," she said. "That's a straightforward matter of legitimate equality.
"[Older women] tell me they feel invisible and they literally are invisible on television.
"We need to do something about that because television represents such a picture of who we are as a community."
Clive Jones, chairman of ITV breakfast programme GMTV, said Scott's case showed some sectors of broadcasting had not "caught up with the reality of the industry".
"The overwhelming bias in terms of talent and ability is towards women at the moment," he said. "There is a real scarcity of talent amongst young men, so I think, over time, we're actually going to see this trend reverse."
He said "stereotypical views" remained in some quarters, adding: "They look to America and they look to the tradition of British television, and they think the right model is an older man and an older woman.
"I think they're profoundly wrong.
"Viewers don't care about age, they don't care about experience. They care about the journalism, they care about the professionalism of the presentation."