A moderate approach to food and exercise clearly clicks with her – she’s glowing and doesn’t appear to have resorted to the cosmetic procedures that so many in Los Angeles find mandatory.

Where celebrities lead, the public inevitably follows. Sometimes there are genuinely helpful health hacks to be discovered. I first heard of Pilates in the 1980s because Christopher Lambert, the French-American actor, transformed his physique to play Tarzan in the 1984 film Greystoke by training with London-based Pilates guru Dreas Reyneke. 

It took me years to pluck up the courage and funds to enter a Pilates studio – in those days there weren’t group classes, everything was a one to one. Vanity got me over the line – everyone who did Pilates looked so graceful.

Twenty-seven years later, I’m grateful that I did. Pilates not only tones muscles, it teaches you to breathe properly and transforms your posture, two of the most health-prolonging, ache-relieving gifts you can give your body. 

They weren’t kidding about the half-inch-taller bit. When you stand properly – pulling up from your waist – you grow taller, allow breath and energy to flow around your body more freely, and take the weight off your hips and knees.

That’s another reason why Seymour (and Jennifer Aniston, Elle Macpherson, Nicole Kidman, Gwyneth Paltrow, Julianne Moore and most ballet dancers, who also do Pilates) look youthful: they’re not in pain. 

Pilates is exercise you can do for life – Romana Kyrzanowska, a disciple of founder Joseph Pilates was teaching until she died, aged 90 in 2013, and her posture was as upright as it had been in her 30s. 

It involves weight bearing (your own) and can be cardio, depending on how vigorously you do it – and unlike running or spin you’re unlikely to injure yourself. Much of the above applies to yoga, which so many take up to achieve a “yoga body” but continue because, like Tess Daly at 52, it keeps them supple and lithe.

Maye Musk, the 73-year-old model and mother of Elon, is another famous person whose advice I’d heed, partly because she’s a qualified dietician who oozes good sense (she’s a vocal critic of finicky diets that eliminate whole food groups) but also because she’s such a good advert for what she does. 

“Plan your meals. Because if you don’t plan, the wheels fall off,” she says. She eats a bit of everything. “Lots of fruits and vegetables, whole grains, good oils, as well as avocado, vegetarian at home, and meat, fish, or chicken when I go out. It’s also because I’m a bad cook.