Joan Collins looked incredibly glamorous in a strapless dress as she enjoyed lunch with Elizabeth Hurley’s son Damian in St Tropez on Monday.The 93-year-old actress showed off her age-defying appearance in a stunning Instagram snap.Joan flaunted her flawless features as she sipped on a glass of wine while treating her friends to lunch.Damian revealed his close bond with his mother’s partner Billy Ray Cyrus, 64, as they smiled for a sweet photo. Joan and Elizabeth, 61, have had a close-knit friendship spanning decades. They played mother and daughter in the E! drama series The Royals. Elizabeth flew out with her son and Billy last week to spend time with Joan at her villa in St Tropez, which she has had for three decades. Joan Collins, 93, looked incredibly glamorous in a strapless dress as she enjoyed lunch with Elizabeth Hurley’s son Damian in St Tropez on Monday Damian revealed his close bond with his mother’s partner Billy Ray Cyrus, 64, as they smiled for a sweet photoShe purchased the five-bedroom property in the early 1990s and has spent three to four months there every summer for more than 30 years.Throughout her career, Joan has offered a glimpse at the regime that’s helped to maintain her famous looks, and she’s insisted it has nothing to do with Botox or any other plastic surgery.Joan has shared that as she’s gotten older, she’s learned that one way to maintain her figure is by ‘eating less’, and said she now eats a quarter of what she did when she was 25.The star said that she hopes she’ll live until she’s 100 with her healthy lifestyle, adding she’ll do a quick fix of ‘broccoli and boiled eggs’ if she needs to lose a few pounds.In an interview with The Express, she said: ‘No knives. Had Botox once, years ago. Hated it. I’m an actress, I have to have expression.’You need half the food at 50 as you ate at 25. Half as much again at 75. I’m going to live to be 100, and I am telling you: look after your skin. Never leave the house without make-up. Joan flaunted her flawless features as she sipped on a glass of wine while treating her friends to lunch Joan and Elizabeth, 61, have had a close-knit friendship spanning decades. They played mother and daughter in the E! drama series The Royals (pictured last week) ‘Don’t diet, just eat less. Never drink tap water. If you need to drop a few pounds to fit into something, eat boiled eggs and broccoli for three days.’While she has been captivating audiences for decades, Joan’s fitness and nutrition have been just as enduring. ‘My exercise regime has changed a lot over the years. I was very active as a young girl. From the time I was 16, I went to discotheques, dance halls, and nightclubs and danced the night away for hours and hours,’ she told Platinum magazine.After that, she would do a lot of gym workouts and Pilates, but admitted as you get older you ‘cannot put that amount of stress on your body’.In fact, she had to scale back her movement in recent years due to a trapped nerve, which led to her not being able to function for two months.