There are huge variations not just in health and life expectancy but in lifestyle, circumstance, needs, hopes, interests and desires. They should all be equally respected.

When I ask commentator Susan Jacoby, author of Never Say Die: The Myth and Marketing of the New Old Age, about my dilemma of feeling caught between midlife and old age, she challenges me.

“Why is it so important to place yourself in a category – what does it matter? I don’t think 61 is old or middle-aged. Why is it important to classify yourself? You say you do yoga. There are all kinds of people who are 10 years younger than you who can’t do yoga and 20 years older than you who still do yoga.”

She says the word “old” has a pejorative connotation but feels group classifications are pointless. “I think feeling you have to label yourself in this way is in no way productive.”

At 76, she is among the oldest of the baby boomers and was a young woman coming of age in the 1960s when the youngest of the baby boomers, like Barack Obama who is 60, was born. “People my age have a lot less in common with the younger baby boomers. I came of age when he was in the cradle.”

Personally, I feel a greater sense of freedom in my 60s. I began to really start thinking about how I want to live because I know life is finite. I know a lot depends on health and socio-economic circumstances, but if you are lucky enough to feel well, with no major health conditions, and you’re not desperate financially, there is a lot to be said for growing older. It’s a privilege denied to many.

I mean no disrespect to those older than me by saying I don’t want to be lumped in with them. I love Helen Mirren, 76; Judi Dench, 87; Jane Fonda, 84; and Joanna Lumley, 74 – but they don’t represent me. Role models at the other end of the scale like Beyoncé and Emma Willis don’t speak for me either.

I told one of my best friends that I was writing this article. She has a big job for a major international company. But despite her important, influential role at work, she is still reduced to being seen as an elderly woman by the mail drops through her home letterbox.

“I started getting lots of stuff about writing my will in my late 50s which I thought was a bit of a joke. Now as I continue to get it at 63, alongside stuff about retirement homes and equity release, I’ve started to feel really insulted.

“The goalposts have moved since our parents were this age. Then, at 60, you would retire and get your carriage clock. We don’t look the same as our parents looked, I would never have worn anything my mother wore, but my daughters are always borrowing my clothes. In some ways, I feel so liberated. I don’t feel defined by my age, so it is irritating when others do so. It is annoying to be lumped under the word ‘old’ because it is so negative.”

According to Emma Twyning, director of communications at the Centre for Ageing Better, it is a thorny issue.

“The notion of being old is relative. Research suggests that as you get older yourself, you keep pushing back the age at which you consider ‘old’ to be,” she says. “Different cultures consider old age to begin at different times. Our research with Ipsos Mori (18,262 adults aged 16 to 64 polled in 30 countries) shows that in Spain you are considered old when you reach the age of 74, whereas in Saudi Arabia and Malaysia, old age comes decades earlier, at 55 and 56. Pythagoras divided life into four phases of 20 years each, with old age beginning at 60.

“The obvious marker for old age is retirement age. It follows then that much of the way we segment people in society talks about the group 65-plus. But this is problematic, as it tends to make us think about older people as one group, separate in society.

“We know people aged 50-plus are responsible for half of all consumer spending, and yet people in older age groups are relatively absent in marketing campaigns for everyday goods and products. Why aren’t marketers doing more to reflect the hugely diverse consumer base that exists at older ages?

“There is a serious point that underlines all this – we are an ageing society. Increasing numbers of us are moving into our 50s, 60s, 70s, 80s and beyond. As individuals, many of us are shrugging off the expectations society has for us based on our age, and yet we know that ageism is hugely prevalent in most aspects of our lives.

“We still don’t build houses with older ages in mind – we think about first-time buyers. Half of people think UK society is ageist and one in three people in their 50s and 60s say their age disadvantages them in applying for jobs. The Government doesn’t even have a strategy for managing the ageing population and the huge demographic shift we are undergoing. We need to start thinking differently.”