She was nicknamed the “thinking man’s crumpet” in her youth. Now Dame Joan Bakewell is to become Gordon Brown’s czar for the elderly, championing the rights of pensioners and the benefits of active living.

Bakewell, 75, who epitomised cool, intellectual beauty during the 1960s as one of the first high-profile female broadcasters, has been recruited to scrutinise policy and ensure that it does not discriminate against the old.

However, Bakewell has made it clear that she will not be content simply to comment on policies affecting her generation, but also wants to “celebrate the achievements of older people” and help the middle-aged to prepare for decades of active living.

“I don’t want to be the government spokesman on how government bureaucracies are betraying the old,” she said.

“It is hard for younger people to imagine being 70. But when you hit 50 you have to address the fact that you are likely to have 30 more years of living to be done and it’s not just a downward decline towards retirement at all – it doesn’t have to be.

“When you have lived from 20 to 50 you think that’s the bulk of life and after that you are on the downward slope – by no means is this the case.”

Harriet Harman, the deputy Labour leader and equality minister, is to announce Bakewell’s appointment this week.

“Joan is a champion in the fight against discrimination against older people and a role model for active and positive senior citizens. So I am delighted that she’s going to contribute to the equalities agenda and be a voice for older people,” Harman said.

Bakewell, who was made a dame in this year’s Queen’s birthday honours list, has a history of breaking through barriers and hopes are high that she will be able to knock down prejudice against elderly people.

She came to prominence by challenging the dominance of male presenters with programmes such as Late Night LineUp, a chat show whose guests included Karlheinz Stockhausen, the composer, and Allen Ginsberg, the poet.

She went on to host the documentary series Heart of the Matter and in 2001 wrote and presented Taboo, a series about censorship that dealt frankly with sex and nudity on television.

Bakewell has also sprung surprises in her private life. She revealed that she had conducted a seven-year extra-marital affair with Harold Pinter, the playwright.

There are no signs that Bakewell’s creativity is slowing down – her debut novel, a romance set in the second world war, will be published next year.

“There are screeds of creative people over 60 just batting on like John Mortimer and Paula Rego and Michael Frayn. You come into your own as a wiser writer when you are older. I am still working at 75 and I know a lot of people who do,” she said.

Bakewell said the elderly often make more reliable employees than younger people. “Old people turn up, they don’t get drunk and have hangovers, they don’t get pregnant, they don’t ‘just not feel like it’. They do what they are expected to do.” she said. “Old people are reliable. When B&Q made a point of deliberately employing overfifties, absenteeism fell.”

She added that elderly people were not as prudish as many thought, but she was concerned by the lack of respect shown to them by the young and the middle-aged.

She pointed to the BBC row over Russell Brand and Jonathan Ross, who left obscene messages on the answerphone of Andrew Sachs, the 78-year-old actor.

“I thought it was vile,” she said. “It was a horrible thing to do. It amounted to harassment. We don’t want people telling grandparents what their grand-children’s sex lives are about. Older people want them to have lively and vivid sex lives but don’t want to be told the detail.”

Bakewell, who said she practised Pilates, the muscle-toning exercise system, added that the young should take steps to ensure “the avoidance of ageing”.

“I would really like people who are young to realise this affects them, that they are going to have this vast life rolling out before them,” she said.

“I am a great believer in getting ready for old age. People can make a positive effort to stay fit.”

A spokesman for Help the Aged welcomed the appointment, saying: “Joan Bakewell played a fundamental role in breaking down gender barriers – we hope that in this new role she can help to break down the barriers to equality that so many older people face.”

Highflying pensioners

­ Earlier this year Colonel Michael Cobb, 91, became the oldest person to be awarded a PhD from Cambridge in honour of his work mapping British railway stations

­ In May, Min Bahadur Sherchan, 76, became the oldest person to reach the summit of Everest. The Nepalese mountaineer broke the record by five years

­ Patricia Rashbrook from East Sussex became Britain’s oldest mother after having her fourth child at the age of 62 in 2006

­ The proportion of over65s in the population is forecast to grow from the current 16% to 23% in 2031

­ The Office for National Statistics forecasts that men’s life expectancy will grow from 77.2 years to 80.7 years by 2025; women’s will go up from 81.5 years to 84.4 years

­ Poor treatment of the elderly was highlighted by research earlier this year showing half the residents of old people’s homes were drugged to suppress dementia symptoms

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