The secrets to 51-year-old Princess Mary of Denmark’s age-defying figure

Princess Mary of Denmark showcased her age-defying physique in a figure-hugging swimsuit on Tuesday while enjoying a refreshing dip in the ocean during a family holiday to Ibiza.

Soaking up the sun on the Spanish island, the Australian-born royal, 51, opted for her one-piece olive bathing costume by Danish brand Copenhagen Cartel. She previously wore the garment on Sydney’s Palm Beach in December 2022. 

Showcasing her enviably-toned figure, the mother-of-four looked much younger than her 51 years as she enjoyed a day at the beach with her husband Crown Prince Frederik of Denmark.

Her youthful appearance is in no small part thanks to a dedicated fitness and diet regime that likely keeps the future Queen looking and feeling her best. 

One of the ways in which Princess Mary stays looking fit and young is through a targeted exercise regime that includes walking, jogging and horse riding. 

‘Mary, like the rest of her family, is totally dedicated to exercise. She’s always walking, jogging, or riding a horse,’ her sister-in-law Leanne Donaldson previously told New Idea.

This was clear during the Princess’s recent family trip Down Under for Christmas, when Mary was spotting both jogging around Sydney with her son and diving headfirst into the waves at Palm Beach.

Over the years, the royal has been spotted trying her hand and succeeding in a number of sports, from tennis to charity fun runs. She also reportedly has a personal trainer to help her stay in shape.

Meanwhile, when it comes to her diet, reports have suggested that the Australian-born royal has the ‘Danish diet’ to thank for her long, lean physique – a regime that is centred on locally sourced and readily available natural foods.

‘People living in Denmark tend to eat more fish, especially oily fish like salmon and less meat than a typical Western diet,’ Sydney-based dietitian Lyndi Cohen previously told FEMAIL.

‘In the “Danish diet”, the emphasis is on high quality meats when meats are eaten – and lean options.’ 

A closer look at the diet shows Danish people typically have a lower intake of carbohydrates and a higher intake of good fats like nuts and seeds and protein.

‘The Danish diet includes fruit and encourages snacking on berries, which are high in antioxidants that can protect against disease,’ Lyndi said.

‘It also includes plenty of root vegetables like carrots, parsnip and potatoes, while rye bread is a staple food in the diet – principally because it it much higher in nutrients like the B group vitamins, Iron, phytochemicals and magnesium.’

‘Rye also contains considerably more fibre than white options, which can support heart health,’ she said.

The dietitian explained that if Princess Mary is following the ‘Danish diet’, then she is likely to be snacking on plenty of fruit and vegetables and eating lots of oily fish, potatoes, nuts and seeds and cheese.

However, while Mary is reportedly disciplined, she is not overly so, as the Princess has been spotted regularly enjoying lavish dinners and glasses of red wine. 

Princess Mary and her husband are taking time off from royal duties with their four children, Prince Christian, 17, Princess Isabella, 16, and Prince Vincent and Princess Josephine, both 12. 

Mary and Frederik were spotted taking a break from the children and their luxury yacht when they took a dinghy to a beach with another couple.

The loved-up pair look relaxed as they swam, chatted and laughed together in the calm and clear water. 

Once on shore, Mary covered up with a bright yellow button-up shirt and khaki shorts while Frederik paired his shorts with a blue T-shirt. 

The princess protected herself from the sun with a white Panama hat and Wayfarer-style sunglasses.  Mary didn’t skip the accessories with gold layered necklaces and a Jerome Dreyfuss leather phone bag. 

Her sporty swimsuit – which includes a two-layer fabric for ultimate support and fit – features a chic square neckline, adjustable skinny straps and seam detailing around the top.

The family’s holiday comes after Princess Mary’s eldest son Prince Christian shocked royal fans with a bold announcement ahead of his 18th birthday.

The young prince, who will celebrate his 18th on October 15, will break protocol by forgoing his royal allowance to instead focus on his education. 

While the future Danish King is entitled to government funding once he reaches adulthood, he will not accept payments and become a full-time royal until he is 21 years of age.  

A statement to the Royal House’s Instagram page said: ‘Prince Christian’s main priority in the coming year will be the completion of the Prince’s upper secondary education.’ 

‘It has thus been agreed with the Ministry of State that support in the Danish Parliament for a law on annual pension will only be sought when the prince turns 21 or by a possible change of the throne, if it takes place before.’ 

The statement concluded by saying Christian will refrain from the spotlight but one day return to making public appearances in an official capacity. 

‘Only after this is the expectation that His Royal Highness will participate to a greater extent in official contexts,’ it said. 

‘However, it depends on where the Prince is at this point in his education. Until then, just like today, Prince Christian will only participate in official contexts to a limited extent.’

Although he has made many public appearances alongside his parents and siblings, Christian is not yet a full-time working royal.