When the former magazine fashion editor Alyson Walsh began her blog, That’s Not My Age, nine years ago it was as a reaction to the fact that she “wasn’t seeing anyone that looked like me in the media, and I wanted to celebrate the fact that older people are cool too and you don’t just disappear off the radar once you’re over 40”.

Now 53, Walsh has witnessed a welcome sea change in the ensuing years, with the media seemingly awash with images of women celebrated for their mature years.

Earlier this week, 73-year-old model Lauren Hutton was revealed as one of the stars of the new Calvin Klein lingerie campaign, having appeared on the runway for Italian fashion house Bottega Venetta in September. Last year high-street retailer H&M cast 60-year-old stylist Gillean McLeod to model its swimwear, and this season, 63-year-old New York university professor Lyn Slater, known to her 111,000 Instagram followers as Accidental Icon, is the face of Spanish retailer Mango’s marketing campaign, “A story of Uniqueness”.

Amber Valletta, one of the original 1990s supermodels, appears on the current cover of British Vogue – reassuringly without a coverline championing her 43 years. She also appeared with many of her contemporaries, including 50-year-old Cecilia Chancellor, in designer Dries Van Noten’s Paris catwalk show earlier this year. Meanwhile, at London fashion week, designer Simone Rocha and casting director Piergiorgio Del Moro invited Jan de Villeneuve, 70 (who has previously worked with David Bailey and Norman Parkinson), 73-year-old Italian model Benedetta Barzini (a favourite with Dolce & Gabbana) and 53-year-old French beauty Marie-Sophie Wilson to showcase her collection. I could go on, but you get the gist.

“The majority of women want to look good, regardless of age,” says Walsh, who claims her style blog is “for every woman who refuses to be invisible”.

“I am 53 and simply want to look healthy, stylish and modern, not younger. And I want to be relevant, even with my wrinkles. We are important role models to younger women, and I love looking to older women who are leading the way. Finally, some brands are talking to me, but it took them a long time to catch on to the power of the silver spend.”

It is predicted that by 2018 there will be 20 million over-55s in the UK, making up one in three of the population. Over-50s already account for around 47% of all UK consumer spending, so there is an economic incentive for businesses to target mature customers.

“Not only are today’s over-55s wealthier, they are also healthier and have more time to spend their money before and during retirement,” says Ina Mitskavets, senior consumer and lifestyles analyst at Mintel. “All these factors are contributing to a rise in a mature demographic of shoppers eager to explore all the options available to them.”

Over-65s spend £6.7bn a year on clothes in Britain, yet it is only recently that this age group has appeared in advertising campaigns for products other than insurance policies or stairlifts. Two years ago, Rebecca Valentine launched Grey Model Agency and now has 300 men and women on her books. “In the last six to 12 months we have received lots more briefs and bookings from cooler brands in the fashion, beauty and travel sectors,” says Valentine. “But it’s still important to have an element of aspiration: even older models must be exceptional looking. They need to appear fit and healthy, with glossy hair and clear eyes. The view of wrinkles is changing: now clients are looking for radiant complexions and don’t mind the lines.”

One of Valentine’s signings is Frances Dunscombe, an 84-year-old former secretary who next month will appear on the cover of a major fashion magazine, surrounded by models of various ages, in a celebration of modern femininity. Having never modelled before, Dunscombe joined Grey at its inception, and has since walked the runways of London fashion week and embraced a range of fashion shoots and TV work.

I’m travelling the world, wearing amazing clothes, being pampered and meeting fascinating people Maye Musk, model

Conversely, 69-year-old Maye Musk is a veteran in front of the camera and on the runway, having worked as a model for the past five decades. Mother to Tesla founder and SpaceX entrepreneur Elon, and grandmother to 10 children between the ages of four and 14, Musk’s main career as a dietitian was supplemented by “regular jobs doing commercial catalogue modelling” – something she began at the age of 15 in South Africa. At 60 she stopped dyeing her hair, cut it short, and her career soared, modelling for Virgin America, appearing in music videos and acting as an ambassador for Swarovski.

“People are being creative with me these days and I love to do exciting work with really visionary stylists and photographers,” says Musk, now based in LA. “I’m doing what every woman dreams of doing at this age: travelling the world, wearing amazing clothes, being pampered and meeting fascinating people. It’s such fun. As long as I’m in good health and am in shape and people keep asking me to do it, I’ll keep going.”

Musk, who boasts almost 35,000 followers on her Instagram feed, attributes much of her success and that of her modelling contemporaries to the rise of digital media and the democratic power of the internet. “Social media has given all women a voice and platform,” she says with youthful vigour and the accrued wisdom of someone who has witnessed life without tablets and smartphones. “Twitter, Facebook and Instagram have done wonders for me, and I love being able to share my experiences directly with those who are interested, and engage with them.”

The surge in street style blogs and mature Instagram “influencers” has allowed consumers to find their own “real-life” style icons – as opposed to professional models in glossy magazines. It has made celebrities and cult figures of a swath of women who might previously have lived a low-key, parochial existence, but who are now feted for their looks and lifestyle and are reaping the financial rewards.

“Women today seek out bloggers who have a similar lifestyle to them, whether that’s an older woman with a fabulous career wardrobe or a bohemian retiree, and we use them as real-life style advisers,” says Kim Winser, founder of fashion label Winser London, which has loyally used 52-year-old Yasmin Le Bon as the brand’s “face” since it launched in 2012. “That desire to engage with relevant but aspirational role models has slowly been picked up by casting agents and brands who are gradually building that into their business strategy – not before time.”

Debra Bourne, co-founder and director of All Walks Beyond the Catwalk, lobbies for increased diversity in the fashion industry. She is encouraged by the recent wave of older faces in the media and concurs that the internet has been a force for good in this context.

“It’s exciting to see a whole generation of older self-selected ambassadors who have become digitally literate, with a lot to say,” says the 53-year-old, who was awarded an MBE for “services to diversity” a fortnight ago. “They lived a life before the internet, and they were without a platform until recently. The media world had written them off as they didn’t comply with their commercial mindset that insisted on promoting a singular youthful ideal.

“I would still like to see advertising and marketing shift towards a proposition built on a wider set of values than purely appearance, particularly in that older market. I am slowly seeing a shift where marketeers are recognising attributes and achievements of individuals rather than just the way they look. By the age of 50, we have lived for a sizeable amount of time and most of us have had some incredible and interesting experiences, which mean so much more than sublimely coiffed grey hair.”

AGELESS STYLE ONLINE

Coco Chanel once quipped that “after 40 nobody is young, but one can be irresistible at any age”. Social media has given rise to a generation of irresistible older style icons with big followings:

Saramaijewels

Australian Sarah Jane Adams, 62, joined Instagram to promote her jewellery business, but her colourful, slightly dishevelled style rapidly attracted a following. 149,000 followers

@baddiewinkle

Great-grandmother Helen Ruth Van Winkle from Kentucky, became an internet sensation at the age of 85. Now 88, the pastel-clad raver hangs out with Miley Cyrus and recently became a muse for makeup brand Urban Decay. 3 million followers

@iconaccidental

63-year-old Professor Lyn Slater became an unwitting fashion plate when she was spotted walking past a runway show en route to meet a friend for coffee. Now she’s the face of Spanish chain Mango. 112,000 followers

@anna_dello_russo

This 54-year-old Vogue fashion stylist boasts a serious designer wardrobe, but wears it with youthful vitality. 1.3 million followers

@advancedstyle

Created by street style photographer Ari Seth Cohen, Advanced Style is a collection of images of stylish older women from around the world. 194,000 followers