Keira Knightley's timeless appearance! Experts reveal how the stylish actress has found the elixir of youth- as she becomes the face of joyous new Waitrose Christmas ad

She first rose to stardom in the early 2000s as the fresh-faced blonde in Bend It Like Beckham before capturing the nation's hearts as a sweet newlywed in Christmas romcom Love Actually.Now, more than 25 years since her first big break, Keira Knightley is one of Britain's few actresses that can successfully span cinema, period dramas and, most recently, Christmas adverts.In this year's festive short film for Waitrose, Keira and Joe Wilkinson both reprise their roles in a follow-up to last year's ad that saw the latter play a glum widower, Phil, who bumps into Knightley at the cheese counter in their local Waitrose.After 12 months of waiting to see what happens next with these two star-crossed lovers, viewers finally find out whether this is the Christmas that Phil gets his girl.Walking through the supermarket aisle in a stylish bomber jacket and scarf, many watching couldn't help but notice that Keira, 41, has hardly aged a day.From her flawless skin to her stylish wardrobe and signature haircut, Keira has developed a repertoire of beauty regimes that help her turn back the ageing clock.According to stylist Caroline Baxter, the 'secret to Keira Knightley's enduring, almost ageless style is that she has never felt the need to reinvent herself'.Below, the Daily Mail learns from the experts how the acclaimed actress continues to appear ever the vision of youth amid her latest festive appearance... More than 25 years since her first big break, Keira Knightley is one of Britain's few actresses that can successfully span cinema, period dramas and, most recently, Christmas advertsAn 'effortlessly' chic hair evolutionEdward James, celebrity hair expert and founder of Edward James Salons: There's a real effortlessness to her hair, and I think that's a huge part of why she continues to look so youthful. Keira is pictured here in October 2010Edward James, celebrity hair expert and founder of Edward James Salons: There's a real effortlessness to her hair, and I think that's a huge part of why she continues to look so youthful.'Keira has experimented with different colours throughout her career, including those beautiful warmer blonde shades we saw in Love Actually, but she's predominantly returned to rich chestnut and deep brunette tones, often with soft golden highlights. 'What's clever is that she consistently chooses colours that complement her skin tone and brown eyes, rather than following trends.Her appearance in the new Waitrose Christmas advert is a perfect example of this. She's very much still a brunette, but there are lighter, warmer tones around her face, which help illuminate her complexion and soften her features. 'It's a really clever colour technique because you're getting the brightening benefits of blonde without losing the richness and depth of brunette hair.'Raul Torres, celebrity hair stylist at BACKSTAGE Chelsea, added: 'Keira Knighley seems to have barely changed over the years, and while we can't take all the credit away from her good genes, her hair certainly plays a part!'She's experimented with plenty of different styles, from long, relaxed waves to shorter, textured bobs, but there's a common thread: her hair always looks soft, healthy and natural rather than overly styled. 'I think one of the biggest lessons we can take from her look - don't try too hard. Hair doesn't need to be perfectly styled to look good. A little texture, natural movement and a flattering cut can make all the difference.'A timeless sense of style Celebrity stylist Lisa Talbot shared: 'I think what's interesting about Keira Knightley's style is that she has managed to evolve without losing her identity & her personal style'. Keira is pictured here in 2010Celebrity stylist Lisa Talbot shared: 'I think what's interesting about Keira Knightley's style is that she has managed to evolve without losing her identity & her personal style. 'She's not someone who seems to follow every trend or completely reinvent herself every season, and I think that's important.'When we look back at her earlier years, her style was very much of its time. As she's got older, it's become more sophisticated and considered, but she's still kept that feminine, slightly playful edge.'She wears a lot of classic pieces, beautiful tailoring, tweed, interesting dresses and lovely textures. 'I also think she understands what works for her. You don't always need to be wearing the latest trend to look current. Sometimes it's about finding the shapes, colours and styles that suit you and wearing them with confidence.'Ms Baxter noted: 'While fashion trends come and go, Keira has remained remarkably consistent, cultivating a signature look that has barely changed over the years.'Her approach to fashion is understated. She favours a classic palette of black and white, occasionally introducing a print, but rarely chases directional trends or dresses to make a fashion statement. 'Her long-standing relationship with Chanel has undoubtedly reinforced this aesthetic. A brand ambassador since 2007, when she became the face of its Coco Mademoiselle fragrance, she has developed a natural affinity with the house's refined, Parisian approach to dressing. 'There is a innate elegance to the way she dresses, with a preference for beautifully cut, feminine pieces that feel timeless but cool rather than fashionable for a single season.' Radiant skin and makeup looks that 'preserve what is already there' Stylist Caroline Baxter added: 'Keira (pictured in 2022) favours wearing soft browns, taupes and nude tone, with the occasional classic red lip. 'She understands what suits her and, importantly, knows not to change it'Mr Aftab Siddiqui, consultant plastic and cosmetic surgeon, said: 'Keira has maintained a youthful appearance that hasn't dramatically changed her facial characteristics over the years. 'Genetics, a balanced diet, water intake and a healthy lifestyle can really make a difference in someone's appearance as they age.' Mr Hasaneen Al Janabi, renowned doctor, founder and lead injector at Dr Hass Clinic, shared: 'Maintaining a youthful appearance does not necessarily mean undergoing more procedures. 'Sometimes the best approach is to preserve what is already there, maintain good skin health and avoid over-treatment.'Ms Baxter added: 'Keira favours wearing soft browns, taupes and nude tone, with the occasional classic red lip. 'She understands what suits her and, importantly, knows not to change it.'There is something of the modern-day Audrey Hepburn about Keira. She has that delicate English rose beauty, an understated femininity and an elegance that doesn't rely on following trends. 'She is not about being the most daring or the most attention-seeking. It is about knowing exactly who you are. And that is her secret.' A relaxed approach to health and fitness Anwen Davies, certified personal trainer and fitness expert at FORZA, said: 'I think it is particularly interesting how relaxed Keira (pictured in 2025) seems to have always been when it comes to her health and fitness'Anwen Davies, certified personal trainer and fitness expert at FORZA, said: 'I think it is particularly interesting how relaxed Keira seems to have always been when it comes to her health and fitness. 'She has always been very open in the past about enjoying her food and is on record as saying she has no time whatsoever for diets, which suggests the kind of balanced approach that's easy to maintain. 'There is an important message in here. Long-term consistency in terms of your eating and exercise habits is really important to ensure you properly look after things like your skin, posture and energy. 'As well as declaring her love for food, she has also made clear she does not enjoy the gym. While filming Black Doves, she told Extra that she did around a month of "spy-boot camp" training in jiu-jitsu, boxing and knife fighting, which she described as getting "our bodies to understand how exactly they would do that."'She has also reportedly worked with a personal trainer previously too, so she is clearly not against the idea of working out altogether. 'Keira has also been open about finding life more comfortable than in her twenties. Speaking to Elle in 2015, she said that after pregnancy, labour and feeding her child, she thought "my body is totally amazing", and she has also spoken positively about therapy when she was struggling with anxiety during that stage of her life. 'From a fitness perspective, that matters more than people might expect. Chronic stress and poor sleep can have a negative impact on energy, recovery and how our skin looks, while regular activity is well known to boost our mood and regular stress management.'