In the course of this series, I’ve been largely focusing on the problems around retirement: the aches and pains, money constraints and neverending working life. But in doing so, I’ve been guilty of not painting the whole picture. One of the things I’ve been most struck by, in many conversations with older readers, is the daily pleasure they enjoy – and I don’t use that word lightly.

One grandmother told me: “Last week, I swept across a crowded pub to pick up a raffle prize … with my dress tucked into my knickers! A few years ago I would have been mortified. Not any more. Told ‘em they were lucky it was cold and I had knickers on!” Despite this frankness, she wasn’t sufficiently blase to agree to her name being used in a national newspaper.

I’m in my 40s and conversations with my contemporaries all too often revolve around work worries and personal anxieties. But it is different for the older generation.

In this nine-part, weekly series, Amelia Hill is investigating the dramatic ageing of Britain, and the implications for work, retirement and wellbeing. Life expectancy is growing by five hours a day, bringing huge challenges – and opportunities – and forcing us to rethink the way we live, love and work. We are keen to hear from readers about what ageing and retirement means for you and your family. Whatever your stage of life, help us explore this rapid period of social change which is forcing us to restructure and rethink our professional and private lives; our relationships with parents, children and grandchildren; and the UK’s finances, transport, health system and housing.

Monica Hartwell, 69, is hard to pin down. She finally answers her mobile phone with an apology for her breathlessness: she’s just off to see the structural engineer at the volunteer-run Regal Theatre in Minehead. Then she’s got some work to do for the film society before popping over to the museum, where she sits on the committee.

“The joy of getting older is much greater self-confidence,” she says. “It’s the loss of angst about what people think of you: the size of your bum or whether others are judging you correctly. It’s not an arrogance, but you know who you are when you’re older and all those roles you played to fit in when you were younger are irrelevant.

“That makes one more courageous,” she adds, ticking items off her checklist as she speaks to me while looking at her watch to make sure she’s not going to be late for the engineer. “I do things now that I wouldn’t have dared to do when younger, for fear of being crap at them. Now I try my hand at whatever I fancy and if I’m not as good as others, I don’t care, I’m still learning.” And with that, she’s off.

Research suggests that Hartwell is not alone in her newfound vim for life: sixty-five to 79 is the happiest age group for adults, according to the Office for National Statistics. Last week, research claimed that women in their 80s have more enjoyable sex than those up to 30 years younger.

According to interviews with more than 50,000 people aged 50 and over by the insurer SunLife, 75% are less bothered about what people think of them than when they were younger, 61% enjoy life more than when they were younger, 59% live for today instead of tomorrow and 42% say their life is more exciting.

Despite findings such as these, Cari Rosen, the editor of Gransnet – founded by the same team that created Mumsnet – says society assumes that growing old must lead to dark feelings and even depression.

“The media, certainly many advertisers, would have you believe that ageing is an entirely negative process, but the evidence from our forums shows that this absolutely doesn’t have to be the case,” she says.

“Life experience often brings wisdom, and you are more likely to be in touch with what does or doesn’t bring you joy and to be able to make choices accordingly.”

As the president of the British Society of Gerontology, Prof Debora Price held an international photography competition last year called Ageing: the Bigger Picture. One of the themes photographers were invited to portray was the joys of ageing.

“Two substantial themes came out,” says Price. “The first really notable idea is that joy is associated with social connection: the joy of grandparenting, for example, but also moments of joy even in the midst of poverty and hardship when that human connection is made, full of laughter and fun.

“The second major theme was that with ageing can come a carefree enjoyment of life, an abandoning, when people can be themselves and forget the cares of life.

“Dancing was indeed a recurring motif for photographers as a metaphor for the joys of ageing. So also was the recurring idea that you could play like a kid, let go, sometimes with the kids, but not necessarily.”

However, Price adds, it was very noticeable that fewer than one in 20 images entered into the competition depicted the joys of ageing. “When invited to show us images that would stimulate a conversation about ageing, and offered joy as one angle, photographers mostly turned to other, more sober themes,” she says.

The conversations I’ve had while researching this series suggest that like the photographers in Price’s competition, we are all heavily influenced by the dominant message of a miserable older life – a worn-out decline into dependency.

But for those entering older age, there is a delicious surprise that this message is all too often fake news.

Caroline Lodge interviewed more than 50 people aged between 50 and 90 for The New Age of Ageing: How Society Needs to Change, a book she co-authored. “Most of our interviewees are amazed by the fact that they are enjoying life and that they feel young and normal, sometimes into their 90s,” she says.

But “in attempting to counterbalance the ubiquitous images of decline, it is important not to create new, unachievable oppressions of physically fit, creative, active, adventurous ageing,” Lodge warns. “This model may represent a new tyranny.”

She’s right. The most interesting thing about ageing and joy I’ve discovered while writing this series is that it comes in intensely personal ways.

Dr Andrew Miller is 69 and works voluntarily as a street pastor in Oxford, where he is the chairman and oldest member of the group.

“We are trained volunteers from local churches, who work in partnership with the police, nightclubs and the council,” he explains. “We leave our base at about 10.45pm on Friday and Saturdays, and we finish usually at about 3.45am the next day.

“Our motto is ‘caring, listening, helping’ and we help people in a range of situations. I recently met somebody who had just been to a friend’s funeral and was pretty distraught, and just wanted someone to listen, as do some rough sleepers.”

Miller walks between six and eight miles a night. “I should be absolutely shattered at the end of a shift, but I feel energised instead because we contribute something to people who are struggling,” he says.

“I find it joyous because helping people is part of being really human. I know other retired people who spend their time going on holiday after holiday. But I couldn’t get my joy that way. For me, joy is a byproduct of being kind to people.”